>>534337291
>>534337510
>>534338642
This is a well known wwyd problem. If you discard one 8p and leave the other floating, and later draw 5m, 6m, 8m, 9m, 1s you'll end up having to discard the 2nd 8p, breaking your chance at ittsuu, so the correct discard is 2s.
And even without aiming for ittsuu, 2s is still the optimal discard.