Today all three of mine wyze plugs (different location around the house) went offline. They were all blinking, unplug and plug them back in. Two came back online but the last one just kept flashing (blue light) I deleted it and try to add it back but I’m unable to reconnect to it anymore.
Have you tried moving the plug to a location closer to the router to see if that would help?
There may be tinterference which is causing the plug not to connect.
As for FW, you can always join the Beta Testers group and get the latest FW before it goes live. You can go here: https://wyzelabs.zendesk.com/hc/en-us/articles/360024852172-Release-Notes to see the latest release of the FW for production use.
3 out of 4 of mine went offline today too! I am just going to see if they come back online without touching them.