Quote from the OP:
"On top of that, due to popular demand and more than a few emails, we are working on reopening our PayPal campaign. Those of you who just heard about the game and want a chance to get in on alpha testing will have a chance to do so."
I do not have any more information than you do at this time, but from the above quote it would only be logical to open it back up before the alpha phase. So a rough time frame would be between now and February 5th. I would expect it to be earlier on in that window in order to give more people a chance to buy in.
I am sure that as soon as the Devs have a better idea, we all will.