...

If you are the owner of an Organization in the UCSB GitHub and your account is expiring, make sure to transfer ownership of the Organization to one of your team members.

All that will remain is your free personal account (https://help.github.com/en/articles/types-of-github-accounts#personal-user-accounts) at GitHub.com that is not associated with UCSB. 

...

1. Be sure to transfer or copy all repos you wish to keep out of the UCSB Github to your personal account before your UCSBnetID expires. 
2. Be sure you have a password you know set on your personal github account before unlinking it from SSO (top right >> settings >> passwords and authorization).
3. Be sure to turn off DUO MFA before you unlink your account from SSO (top right >> settings >> passwords and authorization).
4. Then unlink your personal account from the UCSB GitHub by clicking the leave button next to UCSB logo (top right >> settings >> organizations). 
   1. https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-personal-account-on-github/managing-your-membership-in-organizations/removing-yourself-from-an-organization
5. Once unlinked its then possible to link your github account to some other method for authentication and turn MFA back on.
   1. Users switching between accounts at UCSB my need to submit an issue at https://github.com/ucsb/github-guide or ticket to ITS/ETS to revoke the SSO link, however for most users, simply leaving the UCSB GitHub organization should be enough to separate your personal GitHub and make sure its still usable even if you can no longer use SSO with your UCSBnetID.

Can I Continue to use UCSB Github After I Graduate if I am Still Actively Collaborating with People at UCSB?

...