the P5 scheduling requirement. So of course an announcement that "BYU is a P5" would ONLY impact teams that need to find a P5 for this requirement. You're right that there are several teams like Florida and Georgia that have at least one P5 team that they play every year.

But this is not the case for every SEC team. This is not even the case for all but 4 teams as you are implying.

For example, Alabama does not yet have a P5 team scheduled for 2017 (they've only scheduled one OOC game so far). If the SEC were to follow the ACC, if Alabama wanted to, they could put BYU in there and go for an "easier" path to a 4-0 OOC record. Historically, I think it's been at least a decade since Alabama DIDN'T play a P5 in OOC. But as of right now, Alabama doesn't have a choice but to fit in at least one non-BYU P5 into their 2017 schedule.

I'm not saying that if the SEC called BYU a P5 that BYU would play the SEC every year, but it certainly could help BYU to be able to fill the P5 requirement.