I store on 20 amps and have seen many
of the weird quirks. It is not unusual to have the inverter and chargers changed around from what I set them when I left the coach. I store with both inverters off, and one battery charger on. I have had ever combination possible when returning to the coach. What causes it I have no idea. At first I thought it was power glitches, but all of the hanger has new service from the poll to and including the electrical panel. Were your chargers on when you returned? This is where the Nebula app is so handy to be able to check the coach daily.
Did you set the incoming power on the Vega touch to 30 amps? I also turn the usable down to 5 amps as I share with other users and want to use as few amps as possible.
Having experienced 20 amp storage for 18 years, I doubt if you will ever find what happened. If you do please let me know.
The nebula app is one of the first things I check on my phone every morning. Touch the lighting bolt icon and it will give the battery condition of both banks.
If storing like that again, turn the inverters off, they are not needed. If there is a power glitch the inverter aren't running everything drawing the batteries down. Also if the clock on the microwave is flashing (no inverter to keep it going) it's a tale tail sign there has been a power glitch.