This is a topic I’m porting over from Tom Talbott’s discussion on 2 Thess 1:9 (or the second part of his discussion thereof, rather.)
First, a quick check of the textual apparatus to see if there are any notable variants… nope! That always helps simplify things a bit.
Next, a quick comparison of Green’s Textus Receptus with the UBS (since this could theoretically show an alternative in the text that the UBS editors thought was too insignificant to mention–though they’re very broad about what might possibly count as a significant variant, by the way–but which turns out to make an interesting difference that might be genuine. I’ve only ever seen one case where this happened, namely in regard to one of the Synoptic Temptation scenes, but y’ never know… 
) No differences at all in the textual compilation.
Next, cross-checking Green’s two literal translations with Knoch’s Concordant Literal translation. (Knoch appears to have been working from a textual compilation closer to the UBS than to the somewhat more inferior and textually later TexRec–long story about why the so-called Textus Receptus should only be considered a secondary resource–but every once in a while he agreed with the TexRec.) Along the way, I’m looking for some key words and cognates that I’ve learned translators have a tendency to obscure.
v 27: kai kath-hoson apokeitai tois anthro_pois hapax apothanein meta de touto krisis
(The underscore after the ‘o’ designates a long omega, not a short omicron. The ‘o’ in either case sounds like the ‘o’ at the beginning of those words; or like the 'o’s at the start of ocean and omelet respectively. The hyphen after {kath} is my way of representing in English letters that the word is a shortened version of {kata} taking a variant form in front of a word beginning with a hard breathing {h}. It isn’t really the word {kath}.)
Nothing jumps out as a key word, although as usual I note that “judgment” is literally “crisis” in our language. (That’s where we got our word from.)
Not an especially easy translation. The final phrase is easiest: {meta} is “after”, {de} is a weak generic conjunction between clauses or sentences (“yet”, “and”, “now”, weak “but”, that kind of thing). {meta} needs an object noun or pronoun after it; that’s the pronoun {touto}. The fact that {de} splits the prepositional phrase is unusual and probably signifies that {meta} is supposed to be emphasized. {krisis} is just what it looks like, “crisis”. In English we would represent the blunt use of the term (without an introductory article “the” yet obviously meaning something more important than just any ol’ crisis) with something like a capitalized letter. So, “{de} after this, Crisis”. (Not “after this crisis”, in the sense of “crisis” being the object of the preposition “after”.) Or as translators more commonly put it, “after this, Judgment”. Adding an English “the” to “Crisis” would be okay, to help with translating the emphatic use of the word. Underlining or italicizing “after” for stress purposes would be a good idea, too. As to how {de} should be represented in English, that’ll depend on how this phrase is itself used in the surrounding context.
{tois anthro_pois} is a prepositional phrase built from the plural of “the persons” or “the humans”. That part isn’t difficult; but what could end up being a total guessing game for translators is the fact that there is no Greek preposition! (Nor is this the special prepositional form that means “of something” and needs no prepositional terms like, for example, “of”. 
)
{kai} is a super-common conjunctive term; basically like {de} but stronger. Not only can it mean everything {de} could mean, but it can also be combined with various terms later in the sentence to create a comparative conjunction. The good news is that another comparative conjunction form is being used in this sentence, so {kai} is (most likely) just a conjunction connecting the thought with the previous sentence somehow. The bad news, is that another comparative conjunction form is being used in this sentence. (In Greek this is bad news because their comparative conjunction forms tend to inspire insanity. )
{kata} (which looks like {kath} next to that {h} word) is one of those words that’s just annoying. It literally means “down”, and is sometimes actually used that way, but more often it’s used in some idiomatic way to mean any of a bunch of rather different concepts, including “against” or “in accord with”. (Notice, two completely different meanings, though the general rule is that in a genitive prepositional phrase it means the first and in an accusative phrase it means the second. You have to ignore, that in English descriptions of those phrases you’d expect the meanings to be switched around, with the “genitive” being connected to the meaning “in accord with” and “accusative” being connected to “against”. And… now you are insane. Sorry. )
{hoson}, danged if I know. But everyone seems to agree that when combined with {kata} it makes a phrase that in English would mean something like “as” in the first part of a comparative: “as” this, “so” that. The “so” part of the comparison will come later. Which, not-incidentally, hasn’t happened yet in verse 27; which means that it isn’t a whole sentence. It’s got to be put together with verse 28 (at least). We’ll get to that in a minute.
{apokeitai} is the first word that looks rather interesting (instead of just annoying like {kath-hoson}.) It’s a form of a verb with a built-in prepositional prefix (that’s a very normal occurrence, btw), and literally means “from lie” or something of that sort (where by “lie” they mean “lay down” not “tell an untruth”). You may recall in Tom’s discussion of {apo} back in the previously linked thread and its prequel, that {apo} can mean “from” in an explanatory way, like “from the power of His face”, or it can mean “from” in a negatively directional way, like “away from the power of His face”. (As in, “getting the hell away from the power of His face!” Which, btw, is impossible for someone to do in regard to an omnipresent entity. Just a reminder.)
In this case, {apo} almost certainly has to mean “away from”, not “from” in an explanatory sense; this compound verb is only used three other times in the NT, and each other time clearly has that kind of contextual meaning. In fact, it can be a rather positive meaning!–Paul has a wreath of righteousness “layed away” for him by the Lord, the just Judge, Who will be paying it to Paul (and to all who love the Advent of the Lord) in the day of the Lord to come (2 Tim 4:8). A similar expectation is layed away in the heavens, for Paul’s Colossian congregation, in Col 1:5. The lazy servant in GosLuke’s parable of the minas does something similar, expecting to get let off from having to work with the resource he was given by his master (Luke 19:20): he’s laid it away from himself until later.
In all three other cases, the connotation is that of saving up something (as we would put it in English) for somebody; something pretty positive and good in all three cases. (The lazy mina guy gets zorched because he was expressly told to go out and do business with his resource, representing his Master in public until his Master’s return; not keep it safely secure somewhere in a napkin. But from his perspective, one of his excuses is that he was keeping it safely secure for his king. The king notes that he could have put the thing in a bank to safely draw interest instead!–the implicit point being that what the steward really was doing was trying to keep his delegated mina for himself, where he would have power over it.)
So what (possibly or even probably good) thing is being saved up (or laid up, as we might say a bit more archaically in English)? And for whom?
{tois anthro_pois} Well, there’s the “for whom”: mankind (or derivative persons more broadly). Notice that we’ve also now answered the question of what kind of preposition is being implied (but not actually written in Greek) here.
{hapax} This is the adverb “once”. It means one time, in a historical (or at least narrative) sense, although without necessarily excluding future repetitions. (Context may indicate that this is excluded, of course.)
{apothanein} And there’s the “what”, which is being saved up to be given to mankind. It’s a compound word built from {thanat-}, or death; {apo} or from; and a timing suffix. It’s a fairly common word in the NT, and what’s more interesting to me is that the built-in prepositional phrase “from die” is so common. It’s probably a turn of phrase deriving from an older use where what’s happening is coming from a god of death (i.e. Thanatos). The suffix, I’m told, indicates that this shall be happening.
So, not yet translating the conjunctions, we have something like: “{kai} as it is laid up for men once to be dying {de} after this, Crisis…”
So much for the basic translation. Nothing too striking there compared to standard translations, but I wanted to go through the effort step by step for illustration purposes. 
One subtle result of being picky like this, though, is that dying once might be considered a good thing reserved for men.
As it stands, the verse may be witnessing against things like the Greek (and related) versions of reincarnation.
Now, for the next level of context. The opening conjunction {kai} tells us that it’s probably worth paying attention to what was happening previously. (Which is best to check on anyway. ) The previous context is about how Christ is superior to the High Priest of the earthly Temple, in that He enters into the heavenly Temple once to do for all what the earthly high priest has to do over and over every year (and every day, in a way–the yearly day of Atonement was for sake of those sins not covered by the normal sacrificial routine.) Also, instead of sacrificing something else, Christ our great High Priest sacrifices Himself.
The Hebraist thus draws a comparison between what we would expect if Christ has to offer Himself as a sacrifice every year over and over, i.e. that He would be put to death every year, and what actually happened, which was that Christ ({epi} or “above” the {suntelia} or bringing-together of the {aio_no_n} or ages) has now once been revealed for the putting away of sin through the sacrifice of Himself. (v. 26)
Verse 27, which the question was about, now is seen to be explicating this (although we still don’t necessarily have a conjunctional translation for {kai} yet): as it is laid up (or reserved or saved up) for men once to be dying, {de} then Crisis… then verse 28. Which reads something like, “so Christ having been once offered for (or into) the bearing sins of the many, a second time without sin will appear to these expecting Him: for salvation!” (Knoch includes a later textual emendation at the end, “for faith”. But even Green’s TR doesn’t have this.)
This gives us a translation for {kai} now, too: it means a strong “now” in a sense kind of like “therefore”. And the verse we call Heb 10:1 follows suit: “For the Law having (emphatically) a shadow of the coming good things, not itself the very image of those things, year by year they (the priests) offer continuously the same sacrifices, never having the power of the ones drawing near to be perfecting.” (Which means that the {de} must be a parallel conjunctive “and”.)
Personally, I recognize a number of allusions to the Angel of the Presence (the visible YHWH, image of the invisible YHWH, spoken of in Hebrew as a plural singularity–cf chp 1 of EpistHeb) coming to the Temple for the final redemption of sinful Israel. Other readers may not.
But the point in any case is that verse 27 is not being stated for the primary purpose of dogmatizing that people die once and then are judged in the Crisis–although that is also being stated, so it shouldn’t be ignored. The notion of the verse is being stated for purposes of a parallel comparison/contrast very similar to that of St. Paul in other epistles: Christ dies like other men, but whereas for other men, who are sinners, death leads to Crisis, for the sinless Christ death leads to the salvation of those whose sins He sacrifices Himself to bear. He does not come to be judged for His sins; but rather as the sinless Judge to put away sin and to save the sinners for whom He gives Himself in sacrifice.
Or as 1 Cor 15 (among other Pauline statements on the topic) puts it: just as in Adam all men die, so in Christ all shall be made alive.
And I wish I was taking Communion today, after hearing a sermon on all that. 
I wanted a clarification from you if you would be so kind. In the verse where it says, as in Adam all men died this cannot be onl referring to believers as all right?? So then the part where it says, so in Christ shall all be made alive cannot just be referring to believers either correct?? I ask because this seems to be the sticking point where some do not go UR all the way. Does all actually mean all or only believers???
I have to mention it, though, because that verse is the main local evidence people hang on for trying to get out of an exegetical conclusion of universal salvation there.) Rom 5 also has the promise that all those reconciled to God through the blood of the cross shall even-more-surely be saved into His life; which fits together precisely with Paul’s statement in Col 1 that God was pleased to reconcile all things to Himself through the blood of the cross, the same all things which God created and continually holds in existence, explicitly including the rebel spiritual powers.