Four day postage is not four day delivery. For letters, AP quote is 2-6 days, plus your handling time. That is the handling time you set for EVERY ONE of your listings. Presumably that is 4 days. If you're looking at your items using your selling ID distance won't come into it, and 4 days would probably be right.

I would say - "don't attack buyers who you don't have satisfactory dealings with". THAT is why I wouldn't buy from you