Cheque specimen signature to be updated

Summary:
Need to update the cheque specimen from one person to other. As the last day is August 29th; the next payment run is scheduled for September 5th so the cheque specimen will need to be updated by then.

So for the new cheque should be printed will have new person signature, How we can add this?

Templates to be updated:

VAA General USD Cheques

VAA General CAD Cheques

VAA Promo Fund Cheques

Content (please ensure you mask any confidential information):

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):