I assumed that was a rather obvious one and therefore has been reported, but seeing that it is still happening I decided to post a note here.
It happens quite frequently that after mapstart I get thrown back into the lobby during the cutscene.
If I’m lucky I get deployed during the 3 sec warmup so I can actually choose the proper merc (although 3 seconds is quite short to get an overview of your team’s mercs)
If not then I have to wait until the first respawn round.
It doesnt seemt to be related to any mercs or maps so I can’t give you any additional information, sorry.