Just looking and the Sky contract says this.
"How long your Contract lasts
Unless Condition 11(a) or (b) apply or you end your Contract and immediately enter a new one, you must
subscribe to the Service for at least the Minimum Term and you cannot cancel your subscription during the
Minimum Term. If you do not subscribe to the Service for at least the Minimum Term you will breach these
Conditions. The Contract will continue after the Minimum Term unless it is ended according to the Conditions
below. Conditions 5, 6 and 7 will continue to apply after this Contract ends until you return your Viewing Card to
SSSL. If you do not currently take a Sky Premium Contract Pack and you want to add one to your Option, you will
need to agree a new Minimum Term for your Service.
(a) You may end this Contract at any time including the Minimum Term by giving us 7 days’ notice within 21 days’ of
receiving notice from us if:
(i) we or SSSL tell you we are going to change these Conditions under Condition 10(b) and you reasonably
consider that you would be materially disadvantaged by this; or
(ii) we withdraw any Sky Premium Channel, Stand-alone Premium Channel or premium bonus channel
you chose so that you would be left with no standard definition or high definition variant of the
Channel or collection of channels (as applicable) or are unable to receive the content as part of your
chosen Option;
(iii) we withdraw any Monthly Add-on you are currently receiving, unless you can still access the channels
or category of On Demand content you received as part of that Monthly Add-on as part of your
Option; or
(iv) you reasonably consider that you would be materially disadvantaged by any reduction in the overall
level of service of your chosen Basic Pack, or any reduction in the number of Channels within your chosen
Monthly Add-on.
You may end this Contract by giving us 7 days’ notice at any time (including during the Minimum Term) if we or
SSSL break any of the Conditions. If you want to end the Contract for any other reason you may do so at the end
of or after the Minimum Term, by giving us at least 31 days’ notice at any time."
(iv) would suggest you can end the contract early.