@Mad-Spy Why did you choose “Force” in the implementation guidelines instead of roster? (Doesn’t roster encompass the entire list, and force is merely a subset?)
I’m also seeing what appear to be validation issues when following the guidelines with units that can be part of multiple alliances ... and do a Battleline change (without a General requirement). scratches head
We will never be able to make units switch role after selection. BS just doesn't support that functionality.
in terms of multi-allegiance with a Battleline switch on one of them, look at Chaos Marauder Horsemen. They are Slaves To Darkness Battleline, but could potentially be in any of the God Allegiances depending on their Mark.
Having looked over Azyr, I'm having serious second thoughts on the delineation between Allegiance and PBF. It would seem clear that GW have just made their wording incredibly unclear, but that they actually intended for the two to be synonymous.