I agree, that would be an ex-client.


Notice 2004-54 says:
"This notice authorizes income tax return preparers to sign original returns, amended returns, and requests for filing extensions by means of a rubber stamp, mechanical device, or computer software program. These alternative methods of signing must include either a facsimile of the individual preparer’s signature or the individual preparer’s printed name."
https://www.irs.gov/irb/2004-33_IRB#NOT-2004-54