question for the solar gurus

You're charge controller is doing exactly as it should.
It will charge at 14.4 until it sees the current flow drop to a minimum amount and then work it's way to float.

Richard

How long does the controller hold 14.4 before dropping to float?
What are the charging specs?
Have you turned off any automatic equalization?
I assume no temperature compensation?

Yes could be a bit on the high side for TX summer. Probably fine in winter. AGM actually has a very slow self discharge. You could fully disconnect the batteries after a week and just let them sit 4 to 6 months. Always disconnect the solar panels from the controller first if disconnecting the controller from the battery.

Possibly you could upgrade the controller to have fully adjustable settings. Not sure this would be worth it.

If the battery is fully charged and stays that way, blasting the battery at 14 plus volts could shorten the battery life. Charging should stop whenever the charging amps drops to less than 0.5% of the AH rating. For example charging should be discontinued for a 100 AH battery when the charge amps drops below 0.5 amps. Many solar chargers are not capable of making this determination. Most will automatically hold the 14.3 charging voltage for a couple of hours even if the battery is fully charged and the amps drops towards zero.

There is a reason float voltages are set at about 13.3 v.

According to this it should be ok.

https://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdf

Choice is Float while connected or Storage while disconnected (wires off--the disconnect switch still leaves some things on drawing down the battery).

If you store, but leave the wires on, then the OP's solar float method is the way to go.

I am not a guru, but if you don't mind a non-guru reply...

It's perfectly normal. Every night your solar system shuts down, while parasitic draws on the RV continue to use some power and use some battery amps. Every morning your solar system wakes up, senses that lower battery level, and goes into boost mode, then later drops to float mode.

It depends on how LONG it stays at 14.4.....mostly.
It is probably designed that way on purpose.