Cash back not received yet

[#1]

I had the email from plusnet to claim my cashback on 25th November,  duly claimed a few days later (no later than 30th) and had the confirmation screen but no cheque has arrived yet.  Any idea how long I need to wait?  I'm assuming it's been held up with the post over Christmas but thought I'd better check before the link expires in case I need to claim again? 

[#2]

I've just checked on this and your cheque is due to arrive mid-January, apologies if this is later than you expected.

[#3]

That's great,  thanks.  As long as I know it's on the way I'm happy    appreciate such a fast response too.