David,
Thank’s for letting us know. If an online subscription has expired then sometimes it doesn’t want to play ball.
As a backup there is the printable application form, which you found. Also some paypal forms that can be found on the help pages.
However you decide to pay, all the information goes to the same person for sorting online and offline subscriptions and if paying by cheque then your online account will be marked as paid so you can use the full website.
Alan