Thanks for the idea!
You can buy a recurring 1-yr learntomod subscription at learntomod.com
Specifically here: https://www.learntomod.com/sign-up/
You'll be sent an access key at the email you enter on that sign up form. Then, you can login as usual to your learntomod account, click the Account gear icon in the middle of the page, and click add time, then enter your new key.
It is a yearly subscription, so if you don't want to be charged next year, then email firstname.lastname@example.org with your receipt to cancel your subscription. You can do this at any time. In other words, if you want to be billed for just the one year only, then immediately after purchase you can ask them to cancel your subscription -- then you'll still have access to your learntomod server and the website for one full year.