Sky overcharged me by about £5 on my TV Package so I rang them to complain and was on the phone for about 15 minutes - in the queue and whilst the lady went off to confirm that what I said was correct. She eventually offered to give me a refund on our next bill of the exact amount of the overcharge.
I then enquired as to whether they would also give some kind of apology payment in view of the fact that ringing them was so expensive on the premium rate 8p a minute number. She said that they did not normally do this unless someone insisted. I pointed out that they had made the error and that if they had not done so I would not have had to phone them. About a minute later she agreed to also credit my account with an additional £5 ex-gratia (Apology) payment. Happy Days.
I never did tell her whether I had actually used the 0870 number to call them, she clearly made an assumption that I had.
As a long time user of this website and member of this forum I do not like using 0870 numbers unless I have to. I will leave you to guess which contact number I used!!!