I believe it will work however I don't think anyone can confirm with any certainty as it's not completely clear how Accor will reassess status for A+ members come 1st Jan. The cost is so low and the benefit so high I would recommend you try, the cost in your case is around what a single night upgrade to lounge access at a Sofitel would cost.If I purchase the A+ China for the additional 10 bonus nights, will that count towards my current A+ nights (30 bonus + 20 stayed + 10 China) and allow me to re-qualify for Platinum? The cost to join China is significantly cheaper than a 10 night status run!
The reason I believe it will work if you do it now is that I have just done the same thing for a family member who is currently Platinum (from 2024), had 30 nights from A+ renewal early this year and 10+ paid nights. When I added 20 China nights they immediately were credited with the 2 SNUs (for obtaining a fresh Platinum status in 2025) so it would seem to me this will now be valid through 2026.