When to reduce calories

I wouldn’t know how to survive on only 1500 kcal on rest days. Would make me miserable. As long as you eat enough before, during, and after the workout I’d say workout days a good for a deficit. Weight loss isn’t the time for cutting calories around the workout. This typical underfuling before and during but overeating after. Get the work done, fuel accordingly and keep a small deficit in the evening.