The fence doesn't come down per say, more like a temporary hole in the fence. Bidders would only get the bid for that occurrence of lack of bidders, the fence exists for:

"For a period of five (5) years beginning with the Bid Period in which the

ISL is first implemented, or until the carrier takes delivery of its twenty-fifth (25th)

B787 aircraft, whichever occurs sooner"

So, most likely when the 25th 787 arrives Dec. 2015/Jan. 2016 or so.