What does your online account's membership planet section say about your current membership and its expiry date and, if applicable, your next membership and its start date?
Several people seem to be reporting problems with new memberships not starting immediately and not getting the allowances so maybe there is some technical problem and it's not just the usual timing issue with a new membership stacking until the current one expires?
Might be worth logging a query with 48 support just in case.
Hope this helps.