Mea culpa, reading my own post, two things come to mind. Until Bitcoin Core 29.0, we were reserving 8000 WU for the block overhead, it only went down to 4000 WU in 29.0., I should have been counting blocks as full starting at 3,992,001 weight units or more, i.e. 99.8% full (less than 8000 WU left). Per this metric, there were 117,100 blocks full instead of 117,630, which also let’s us deduce that there were 530 blocks that were between 99% and 99.8% full.