When to buy scallops?

Excuse me, could you please clarify when the optimal time is to purchase scallops? I've heard that timing can make a significant difference in terms of both quality and price. Is there a particular season or time of year that's generally considered best? Also, are there any specific days of the week or times of day when scallops tend to be fresher or more affordable? I'd greatly appreciate any insights you could offer to help me make an informed decision.