My work permit expires in 2 months' time, and I am planning to go abroad for 10 days. I will return to the UK one month before my visa expiration date. Is it possible that the border agency officer won't allow me into the UK upon my arrival?
They will look at your wp and ask how long you were out of the UK, and if you are still working for the same employer, and then advise you that your wp will expire soon.
So the answer to your question is you should not expect problems re-entering if your leave is still valid.