Jim, you need to call the shop or Cannondale directly. Their turnaround on a fork rebuild is 10 days (2 weeks) MAX!
If it's been as long as you stated, there is a problem. It may be they have simply lost your paperwork, or the damage is more significant and need your authorization to proceed.
I'd call the shop first, find out what they have to say. Get the RA # from them and then call Cannondale.
When I sent back my wife's fork, I had it back in just over 2 weeks (shipping delay!).
L8R
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