Like count reset after page was temporarily taken offline

The FB Like count on one of our pages was reset to zero after we temporarily took the page offline (we recently reinstated the page onto it's old URL).

I understand from the FB Developer docs that Facebook scrapes our pages every 24 hours; I also understand that Like are linked to URLs.

Why has the page's Like count been reset to zero, even though it has been republished using the same URL? How long after a page is taken offline 开发者_开发技巧does FB consider it to be dead, and reset the Like count?

Thanks for your help,

Alex

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I noticed that FB's debugger (http://developers.facebook.com/tools/debug) was showing a Like count of 29 for our recently reinstated page - even though the page itself was still showing zero Likes. This gave me some hope that the missing Likes might be be added back onto the page.

Within minutes of playing with the debugger, the page's Like count was showing 29.

I'm still no closer to finding out the answer to my original question, but perhaps the FB debugger can help others with similar problems.