I have seen on 3-cabin INTL flights with as many as 6 oversold in business am of the departure. Since F was 8+ seats on these instances, they are either going to upgrade the 6 or with the no-show rate of say 2, then upgrade the 4.

Only once in SFO, flying to HKG have I overheard the GA's mentioning "we may have to downgrade someone from business." YMMV...