I don't think that good old FLA RV batteries are accumulating amp hours when they sit there sucking 1-2 amps for days/weeks on a trickle - or any other - charger.
I think that long before the days/weeks have elapsed ... they are fully charged ... and what they are doing is just sitting there dissipating 1-2 amps of leakage current. RV AGM batteries (at least mine) don't seem to do this, thus making it very easy for me to tell when they're fully charged. I just look for near zero to zero current flow on the RV's built-in coach battery ammeter.