I have not been at that specific Sofitel but other Accor properties in Bangkok seem to do an excellent job with their Platinum valued guests, no reminding necessary, upgrading at least to one room category above booked.

Sofitel Bangkok Sukhumvit has been known to double upgrade their best customers to nice suites, so kay sedia may benefit from the enhanced room/rate already booked.

Bangkok is one of the world cities where Accor properties do seem to sincerely appreciate revenue streaming from Accor elite guests, so, I have also gone out of my way to keep patronizing them.