Add memory card to Ring Stickup Cameras

I use Ring to provide security for my short term rental property...and overall I am very pleased. The external cameras have captured video of guests doing prohibited things that I am able to address before they become big problems. What would be nice, however, is if the cameras had a memory card that would capture those video snippets when the wifi is down, and once the wifi is back up, upload those videos to the cloud based on the timestamp of the video....which is how the base unit and associated devices (door sensors and motion detectors in my case) work. Most of the time it is a problem with the cable provider, but my most recent guests disabled the wifi for a few hours, and I suspect had a banned gathering at the property - but I can't be sure since it was late at night (so no neighbors reported a problem) and there was no video to look at that would tell me who was coming and going. The door and internal sensors certainly indicated something was going on, but I have no way of being certain if that was just the guests enjoying a late night/early morning, or if something worse had happened. Happy to discuss further if this is something you would consider