The White House was given an arbitrary deadline of 5pm tonight (without any background information) for a participation response to a House Judiciary Committee December 4th hearing; at a time when President Trump is attending a NATO summit; for a hearing with unspecified witnesses; and for a hearing with unspecified purposes; and for a hearing with unspecified rules.
The White House responds accordingly (pdf here):

The full five-page letter is below:

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…”How incredibly tragic is it, with all the documents and communications that AG Bill Barr & U.S. Attorney Durham can see today, that they are not acted upon BEFORE the House can brand President Trump with the words “Impeached President” for the rest of eternity.”…

Then again, maybe that IG/Declassification delay is the plan.
An institutional feature, not an inconspicuous flaw.
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