I’ve been seeing different numbers quoted on the internet, 30 days since annual fee post date, 30 days since statement date of annual fee post, 41 days since annual fee post, etc. for the annual fee refund of PCing a CSR.

My annual fee posted 8/1 and 30 days from that is 8/31. I ask because I have a short weekend trip 9/1-9/3 that I could use the trip insurance for and also some travel credits (~$100) to finish using via Uber. So ideally I want to downgrade after that which is more like the first week of September.

is 41 a safe bet or am I risking a prorated refund going past 30 days?