How long will the Tempest Shop NPCs be sticking around for?

I want to spend all my coins, but I've also got a logout gift that keeps popping up every time I log out of a character on my account and I don't want to get it yet :\

When you log out put the client in window mode. When it asks you to select a prize bring up task manager and end maple. Since you didn't select a prize next time you log in it will still ask you to select a prize.

That's what I've been doing, but since Maple takes ~1 minute to start on my computer (it hangs for a while before reaching the login screen) I'd rather wait until I can actually use the logout gift to spend my Tempest coins.