On my flight from STL to LAX they did the usual boarding of F and then elites first, then they asked for group 1. And they made it sound like group 1 was sitting at the back of the plane.

Or maybe it was group 1 and anyone sitting at the back.

I don't know but it really sounded like group 1 was at the back and they were filling the plane from back to front by group numbers.

I'll have to pay attention on Wed to boarding order.