Welcome to the Forum, @stephenmjoseph! 
When Cam v4 launched, the marketing and product page indicated support for microSD cards up to 512 GB (I think that may have been the first official mention of support for that size of card for a Wyze Cam), but that has since been changed to 256 GB for some reason (I haven’t seen an explanation from Wyze). You can still find references to this in the launch announcement, though what I see in the Help Center lists a 256 GB limit.[1][2]
Looking at a Cam v4 with a 256 GB card set for continuous microSD recording, I see that the timeline begins on 20 February 2026, so I concur with @Antonius’s 3-week assessment. 