Good timing that this thread popped up today.
Regardless of the last time that we camped I have always (16+ years) charged my trailer batteries every 3 months. Today being the closest Sat. to 9/30 it was charge day.
I have this battery as well as an older/wimpier group 29 Interstate & an even wimpier group 24 Interstate.
With this battery we last camped 5.5 weeks ago (with Mr. & Mrs. Big E in fact!) and after that dry camping trip I charged this battery up before storing it in the garage.
So, 5.5 weeks ago it was at 12.75 volts. 30 minutes ago when I checked it before charging it (at the 2 amp setting) it was at 12.74 volts (nice!).
It's done and ready to unhook.
*Here is my "Battery maintenance - what works for me" thread -
https://community.lanceowners.org/top...ce-what-works-for-me