So, you are pay protected for TL, but not DC. For lineholders, a lot of conflicts are DCs and thus not pay protected. Pretty easy to lose 10 hours of pay that way. Especially if your first trip of the month has some silly 1.5 hour GRK overnight which they tag on to an already weak end of the previous trip. Most of the time for reserves you want the transition, because you get paid for the TL day off you get. But for lineholders, the transition is a trap and it only works if you have back to back trips. For overlapping trips, transition often works against you.

I had a 19 hour 4-day turn into a 3 hour overnight and 4 hours of carryon. So I lost 12 hours of pay and working 6 days in a row. Never making that mistake(selecting transition) again.