Currently running V11. All is well. Firstly is it worth upgrading to V12 as the only thing I would like is faster GPS lock-on. If I do upgrade will the current 1 year mapping licence I have be removed?
Yes, the license is removed, but when you bought it, you should have gotten a registration code in email (to the email address you provided when you bought the license). Use that code to reactivate the license after a firmware update (or full reformatting of the device).