Very interesting. My wife and I attended an Open Brethren assembly during the 2 1/2 years we lived in Zambia immediately following our wedding in 1966. There were two morning services on Sundays, the first being the “breaking of bread”, the second following about 45 minutes later, a typical Evangelical-style service.
The “breaking of bread” service was unplanned but had some structure to it. Men, women and children attended but only men were permitted to speak. Remember, this was over 50 years ago when women wore hats to church services, their dresses were sleeved, i.e. no bare arms, and hemlines were at least 4" below the knee. And this was in the middle of Africa where the temperature rarely fell below 80 F! Times sure change.
As I said, there was no fixed form of service, but meetings almost invariably followed a pattern, A man would announce a hymn, another might pray, another read a scripture passage, another pick a hymn, another pray, another speak to a passage or a particular verse of scripture, and so on until it was time to gather for the formal second service. You get the message? We quite enjoyed it. Oh, I forgot, there was no collection!