Hello, I'm Keith and happy to help you with your question.
The P85 should be completed notifying the date you originally left the UK, Nov 13. On receipt HMRC will make you non resident for the 14/15 tax year and also split the 13/14 tax year into two portions, one resident and one non resident. On your ultimate return to these shores you merely advise HMRC of the situation and a reverse process will take place. That is the administrative procedure for leaving and returning to the UK. You will retain your non resident status provided you do not spend more than 91 days in the UK in any one tax year. In theory the 91 days can be averaged out over four years, but the general consensus of opinion amongst experts on this site is never to exceed the magic 91 days.
For the period you are non resident I would anticipate HMRC issuing a NT code, but you would be liable to Income Tax for the resident portion so the code might be adjusted in an attempt to make you tax neutral by the year end of your year of departure. The deduction of NI I can only see as advantageous to you as it will keep your card stamped, to use an old expression, and also your State Pension records up to scratch.
Provided HMRC can contact you through the address notified they will not be concerned. When advising the change of address it may well be adviseable to indicate that this is an accommodation address only.
I do hope I have helped you in your attempt to create a non residential status. In fact, administratively, it is relatively simple.
So just to be absolutely clear, it is acceptable to put a UK care of address for correspondence and they will not view this as an address of residence?
And regarding the question on the P85 of having my salary paid from the UK, do I have to answer yes to this as my wages come through a uk agency and uk umbrella company, or is it no because ultimately the employer is not in the UK?