So each day is unplanned as to where you will end up ?. I assume you would be able to research at some point during each day what the potential stopping locations are going to be ?. Maybe do different segments that are just whatever navigation you need town to town, outskirts only. Then don't bother having a navigable route to/from the hotel. Just use the GPS map to see where you are and use it to get to the hotel from wherever that segment ended. Next day just do the same to get to the start of the next segment. I don't know the device you are using so don't know what it's capable of.

Begs the question as to what the pre-planned navigation is giving you ?. You could hit a thunderstorm and have to stop very early, too hot and the same, feeling great and want to extend. Thus the pre-planned Kamoot (or anybody's) route is mostly useless to you. I would think decent maps would be easier and just use the GPS to determine location on the map, then look at the map to find a route to a particular ending point.

If it was a spanking new Garmin 830/1030 unit, they've added a number of features to do pretty much what you are asking, interrupt a navigation, detour, and return easiest way to that route you were navigating. Expensive solution though.