Welcome to the Forum, @mrnikpalmer! 
I’m not sure about the time lapse feature specifically, and I don’t own any Cam v3s, so I can’t test that specifically, but I wonder if that model uses the same folder structure on the microSD card as Cam v4. When I pull the card from a Cam v4 after recording a time lapse, I can see a time_lapse folder in the root directory that contains the recording. I’d be curious if your Cam v3s show this and have anything useful that you could retrieve. (I realize this may not be practical because of the mount heights. I’m just speculating.)
I think the uptime beyond 30 minutes may depend upon which firmware version the camera is using, as demonstrated by @grapefruityoda’s research and posts, helpfully linked by @peepeep! 
The one official mention of this that always comes to mind in this kind of situation is this:
Because of that, I’ve read of some users setting up local NTP servers so that the Cams don’t reboot when a time sync fails, and I wonder if something like that might be an option for wherever you have the Cam v3s installed. This is where an easier decision might be to just choose a different product, depending on the need and use case. 