question

looking at your loads, your peak current is only 15A - leaving worst case 15A to charge batteries. The fridge would likely be at 30% duty cycle, and 'furnace' would probably be a lot less (water heating or air heating?). This should leave plenty of energy for recharging. Depends on your battery capacity, which is not stated.

Also, why drop the Lithiums from 90% to 50%? If 'storage' means you are not using any of the loads or the RV, Litium storage can be anywhere from 50% to 25%; but it's generally not needed to charge the batteries more than once a year if they are disconnected from loads (inc BMS). The charger can then be set to give float charge equivalent to 90% SOC.

I have a small RV with the IP22 (30 amp / 3 circuit).

First, 50% SOC is very conservative - your LiFePO batteries will probably already last 10x longer than your RV, even if charged to 90% or 100%. Many LFP batteries are good for 2000+ cycles, and if you are storing your RV part of the year, you aren't even doing one cycle per day. You don't have to coddle your LFPs.

Second, note that the multi-battery IP22s do not have independent control of all circuits. I have a 3-channel IP22 (of which I'm using 2: one for house LFP and one for lead acid starting battery) and it seems like it bonds the two together. E.g. you can't have different charge profiles for each battery. If you can find a happy compromise between Lead Acid and Lithhium profiles, the IP22 is great.

I had mine set up to float at 13.2, and vampire loads were causing the LFP house battery SOC to drop to under 80%. Since I think of my RV more as a "emergency vehicle" I wanted it to be at 100% all the time, so I bumped up the float voltage to 13.5.