The freeze-up is supposed to end tomorrow :) Anyway, the WFCO is a modern type converter and can run the rig with no battery. It can also maintain and charge the battery as required on shore power.
If you cannot trust the shore power in storage, take the batteries home and put them on a simple maintenance charger and keep an eye on them at home. If you can trust the storage power, leave them on the WFCO.
If you ever go off-grid, and the WFCO does not go into 14.4 for fast charging on generator (many won't as installed too far from the battery bank), NOW you have a problem.
That can be solved by getting a different or additional (several choices) battery charger that can be run by the generator's rated continuous VA. The new (portable is a choice) charger will do the required fast charging --two 12s will take say a 70 amp charger no problem--you can use any deck- mount converter as your portable instead of installing it.
If you do not camp off-grid except for a day or two, you just need new batteries and you are good to go using the WFCO as before.