Rolling 20, while asking for an instructor change may be a good idea in some cases, I would hesitate to suggest this without a good deal more information. For a start, we don't know how many instructors the Daverehm has already had, what he or she is learning on, in what sort of environment, how often he flies, what the weather has been like, and all the other variables. 22 hours is not excessive for a middle aged person coming to a light aircraft with no aeronautical background. I would like to know what the specific difficulty is before making any further comment.