Guyana new signature variety confirmed

This 20-dollar note (Pick 30) from Guyana shows Lawrence Williams signing as GOVERNOR (ag) on a note with prefix B/57, followed by a prefix B/64 note with the title as GOVERNOR. As far as I know, the Williams/Kowlessar signature combination appears only on the $20, $100, and $1,000 notes, although the GOVERNOR (ag) title has been confirmed on the $20 only. If anyone can provide scans of other notes with this signature combination, please do so.

Courtesy of Bill Stubkjaer.