Is it safe to change the Hub backup account associated with an install?

I have a couple of virtual servers being backed up (very nicely thank you) with TKLBAM but they are against my own account so that I could watch the process and check jobs/costs. Now I want to transfer the backup payment and access to someone else.

I had assumed I could change the key and backups would start afresh from the new account?

So questions are mainly around the idea of transferring existing backups to another account and how much, if any, of the existing backups I can access without a download/upload cycle.
 

Off topic slightly but interested to see if I've missed this ability?

Slave machines, if Server A is being backed up to Cloud and also to a local Server B I could in the event of failure promote Server B without having to recover the latest backup from the cloud.

I have backup “SME Server” installs running AFFA and in the event of a failure I can get to last backup and replace the working ~250G server in around 15-20minutes.

Cheers

Stu