Should the person that did your 'hour with an instructor' also be an examiner can he/she sign your license?
If you're revalidating, before the expiry date of the rating, by experience, then if the hour is with a instructor, that's fine, but you must then subsequently go to an examiner to carry out the administrative action. If you fly with someone who is both that may make things a little simpler, but you don't have to.
If you choose to revalidate by proficiency check, because you don't or won't meet the "by experience" requirements, then that has to be with an examiner.
If you don't revalidate before the rating expiry date, then you will be renewing, which is by test, with an examiner.