[beeje]

The first thing I always do when I get a new/used camper is to get it level using a 4 foot level on the floor in various places, front to back and side to side. Once I am satisfied it is as level as its going to get, I install two Hopkins graduated level gauges. 1 on the side and 1 on the front of the unit. Now I will know what level is with just a glance.

With this being said I would not put total faith in the level up screen as to weather the unit is level or not.

Also, as mentioned, if your legs are on soft ground with no blocks under them, they will sink over time. Re-leveling while staying stationary for long periods of time is normal.