Just had the following email:
In celebration of Image Day on 1st of February pre-orders and subscriptions for Walking Dead #163 made before 12 noon on Tuesday 31st January will not be charged.
This comic will also be available for free in our stores on 1st February on a one-per-customer basis. You can find a list of our stores and their opening times here: https://forbiddenplanet.com/stores/
Postage costs and any other comics on your order will be charged as normal and please note, further orders made after this time for this issue will be charged at the regular price.