Leaving Germany on 30.11.2016, cancel Blue All-in L contract

Hallo!

I'm leaving Germany on 30.11.2016 and I would like to cancel my O2 Blue All-in L contract.

I renewed it on 07.03.2016 with a 2 year one while I bough a new mobile that I'm still paying monthly. I would like to cancel the contract and, if possile, still continue paying the installment plan for the mobile. If now I would just make an early redemption of the amount left to pay.

Can you show me how to proceed on this and when would be the earliest cancelation date?

Is there any option to, instead of cancel, keep the contract with the minimum tariff available, and how much whould this be? Just in case it's a really low tariff I could keep it for a while and cancel it afterwards.

Thanks in advance for your answers.