Subscriber records merge?

Occasionally the same person/subscriber may subscribe for several plans under different user names. This means they cannot see their subscriber history. I was wondering if it would be possible to have functionality that allows the administrator to manually merge two subscriber records into one, eg if Joe Blow expired as a member a year ago, then he resubscribes for this year's plan under a new username (rather than renewing the expired plan) it would be nice for the admin to be able to move the old subscription record into his new record so he can see his full history. Is this possible?

Can you not already do this from the Subscriber screen in backend by changing the joomla user id?

As @Calum mentioned, you can just edit the subscription record, select the user which you want to associate the subscription to and it should be fine

Tuan