Miners signal for segwit in their blocks, 95% of blocks signalling for segwit in any single difficulty period (2016 blocks) will 'lock-in' and start segwit enforcement two weeks after that.

_

If lock-in occurs before February '17 this proposition settles as YES.

If lock-in has not occured by 1st Feb '17 00:00 GMT this bet settles as NO,