Tuesday: our glorious leader, President-for-Life Fred, has altered his decree. Pawns on Black squares may not be captured, Pawns on White squares may be.
Wednesday: Fred flips again. Pawns on Black squares may be captured, Pawns on White squares may not be.
Thursday: Fred Flees! All hail the glorious revolution!
Friday: No paper. Fredonia Free Press offices are burned.
Saturday: We thought things were bad under Fred, but now we long for the old days; and so we play a new kind of Chess.
For example, before White's first move, White flips a coin; its result decides the status on WHite's second move; if it comes up heads, White's second move may not capture a Pawn on a light square, but if it comes up tails, pawns on dark squares will be safe. Both White and Black know the result of the coin flip.
If the coin stands on its edge, the revolution has come, and all Pawns vanish from the board. The coin is now useless.
If you don't like the way the game works, feel free to try changing the timing of the coin flip, so that the safety status is known farther ahead or so that it is known less far in advance.