I read the same thing as you and contacted the WAM several months ago to check and that is what I was told. I am lucky enough to be grandfathered in until Oct 2024 and will need a Blue Golf Hcp for the 2025 season. I then double checked last week again before the Q school registration closed and was assured I was OK
With your Hcp ending in June I assume you will have to get another handicap before August but regardless your numbers will transfer over as they are all interchangable and use the same WHS formula the only difference is that the membership fees goes to different entities
I assume that each individual state are pissed that they are losing money to any one/who that offers an online system for hcp which all uses the same information of the WHS. IMO the USGA made this rule to simply look after their own.