Re: coming here to learn and share
Not unusual here to get really warm with lots growing & then a surprisingly late frost or two, tho usually fairly light frosts. I take my overwintered bananas outside in their pots so I can bring them in for the night if there's going to be a frost and take back out the next afternoon. I have one banana that is too large to move around so, once it SEEMS safe, I plant it in the ground and, if a frost gets predicted, use a tall stepladder to straddle the stem & make a framework, cover it with heavy sheets secured by clothespins to make a tent around it, and put a small bathroom heater (the fan blower type, not ceramic) inside the "tent" for the night and it has survived every time. It's some extra work, but it gets my nanas back outside and growing sooner.
Best of luck!