all you can do is go to Phuket Immigration office with a TM30 showing you're registered as staying down there and see if they'll let you apply for a re-entry permit or not
I don't even know if they sell re-entry permits at the Samui airport, and I'd post on a Samui or southern island group and ask
@Stuart ********
do you know if someone can buy a re-entry at the phuket immigration office with a yearly extension from Jomtien ?