Network events like a Bitcoin halving or an Ethereum upgrade are scheduled by block height, not by clock time, so the exact date drifts as block times run fast or slow. Markets that ask whether an upgrade happens 'before' a given date are really asking a question about hash rate and block cadence. You project the arrival block from the trailing block-time average and trade the date markets that are still using the naive estimate everyone quoted months ago.
Markets on Polymarket where protocol-upgrade & halving countdown drift is the natural play:
