In my situation, the refund is just going back to my PayPal account from CDJapan; I'm not withdrawing it or getting it sent back to my bank account (even though that's where the funds originally come from). And pretty much all the times I've gotten a refund from CDJapan, PayPal has put a hold on it for some reason.
It's really annoying because I usually request refunds from CDJapan just so I can make another order but I always have to wait a week to use my money because PayPal puts that dumb hold on it.