Logging with an inactive e-mail?

Hi! Does the username (e-mail) still work when logging in, even though the e-mail itself is not working anymore? We were wondering a situation where a client has an access to a hub with his work e-mail but he quits the job (we might not get that information), so does the client still have an access to the hub even though the e-mail is not working. Of course he cannot change the password anymore, but might still remember the password. Thanks in advance!