Matt, that's not what I'm drawing from the number changes. That said, BJ red-shirting has been a given for a long time barring any injury.
I see it along these lines...
Jerrell switching to 10 (happened yesterday, btw) gives us the ability to have Roy and Jerrell on the field at the same time for special teams duty.
Same with Rogers and Julio being a part of the same special teams grouping.