I dont think that rank means a thing. I was previously a 2nd dan in Wado-ryu with 10 years behind me when I took a ten year break due to work and family comitments. Having started out with a new club (I moved home) and a new style (Shito-ryu) I was more than happy to start at the begining even though my Sensei said I should keep my rank. I truth I have probably learned more having started back from scratch - Your basics, kion and basic kata are the building blocks of all your Karate and I have gained alot from going back to basics. If rank is an issue then you really should look inside yourself and ask why.