I've flown 17 segments so far this year.

I've sat in First 7 times. Of those 7 times, two were FCM, leaving me with 5 upgrades of 15 segments. 2 of the upgrades cleared ahead of time, 3 were battlefield. I missed one upgrade (jfk-las) as they had 6 seats available and I was #7.

Of the 2 upgrades that cleared ahead of time, one cleared about 48 hours out. One cleared at 24 hours out.

The real benefit, as mentioned above, is being able to get EC seats. Of the 10 times in the back, I've only had one time that I had a normal seat. All others were exit picked in advance or I moved into EC either at check-in, or when they cleared the battle field upgrades and I snagged a DM/PM/GM seat.