Well, I've done my wee bit for our list of 50+ members, and received 40 opt-in replies after a bit of nagging, 2 opt-outs, and 10 no replies, who will therefore be deleted. (Not been seen dead or alive for years anyway!)
Been hanging around waiting for directions from parent organisation for what to do about another list of 200+ people that I hold: now,at the 11th-hour + 50 minutes, they come up with a super-lengthy spiel, which basically says "Do nothing and you stay on the list". Just AAARRRGGHH!