Must "Job Well Done" certs be used within one's PM or DM status period?

I didn't have occasion to give out my JWD certs last year, and I'm wondering if they're still valid now that I've dropped down to GM.

Also, are these things as valuable to employees as we like to think? I know a couple of FAs and told them I had some certs I wasn't likely to use before my status changed. Neither seemed the least bit interested in taking them off my hands.