Zas, this may be interesting for you. According to the Wiki (second paragraph) checking daily is a bad idea, nowadays.

Quote:
The current best guess theory is at least a month, up to 6-7 weeks. If you get to the point where they are empty and you keep trying without waiting the appropriate time, it seems they will never reset.


I just checked because of your post, sorry I didn't think of it earlier...
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