I moved from state to state within less than a year and a half - and did the whole re-registering vehicle and DL ... I think once everything is processed, which is pretty much right away, you are good again to move and do the same thing over again. They can't limit the amount of times you do it - and, if anything, they will respect the fact that you are prompt about doing so - as many people move from state to state and do not follow the law and do it within the certain amount of days that you are required to do so. Also - at the very least - they are grateful that you are pumping all of that money into their state - because those license and registration fees add up, I'll tell ya!!!
Don't worry it'll be fine! No one is going to accuse you of running from the feds or stealing an identity.