I’ve never understood the timing or paid attention. I was close to 1K this year so bought a couple of inexpensive (less expensive?) FC upgrades for my usual DEN-ORD flights in December. Looked yesterday and received an additional 1,000 PQP from credit card spend at once. I definitely didn’t have a $24,000 spend in one month.
completely negates the need to purchase upgrades but I guess those flights in December will be in F and 1K. I won’t complain.