I usually make an unfill once a year, because I just feel its good to give that area a rest. Everytime I make the unfill I do tests to check if I have erosion, and eat whatever I want to remember myself how does it feel to eat normally.
When it is time to refill, my Dr. usually fills mty band 2.2 C.C., after a week he finnaly adds solution to 2.7 C.C which is my normal fill level. That way I start getting used to the fill again. I have no signs of erosion or complications up to date.