A nice problem to have.....your lithium install working so well that the genset is a back up system. Agree with Mohammed on the genset during passages; there is obviously a good reason Amel recommends running it daily at sea. We do this even when we don't necessarily need the power.
In the rare occasions we've been long term in a marina, we don't go more than 3 weeks without running the genset based on a boat show conversation I had with a tech on this question. There are probably many opinions on this but following his advice has worked for us.