Im looking for the quickest known solution :

I need to link to over 52 separate workbooks and pull back a number of cells.
the problem is that depending on what week we are in some workbooks will not exist.
but i need the links to stay live then update when the sheets do exist.

Ive tried PULL and although hats off to the creator its to slow for my PC's at work.

Is there any way i can use something like " if TODAY() is greater than 25/10/12 then "standard link to closed workbook" , if not then "" ( problem is because the workbook doesn't exist obviously it returns a REF#

Any help is much appreciated.