Actually it does not need to be connected all the time, my time frame to complete one K is about 4 days using only one cpu running at 2.2 gHz.
When you set up the config button, you can uncheck "transmit intermediate blocks" This will mean it will actually run faster with out the constant need to update the project server.
So your question is yes and no, it can run for a short time offline but it needs to upload and then crunch for another set of time. IF you have a quick machine I suppose you could finish one K in about 30 hours. As of this writing I am unsure if you can down load more then one K to crunch while off line, An email to the leaders of this project gets quick response. That could facilitate the answers you need to make a concerned effort a reality. There emails are available at the bottom of each page on the Seventeen or bust Project, right after the Copyright information...
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