Not sure it is related, but I hit platinum for this year (was gold last two years, previously chairman's) via 91 segments (primarily BOS-PHL flights). I flew to Philly yesterday and my boarding pass says Platinum. This morning, I went to check on something for a UA flight to ORD and it has me as Chairman's not platinum
I've been bumped to Chairman's previously from Platinum, but it was back when BOS-PHL flights were $1100 but am (pleasantly) surprised this morning