Sticky pistons facing different directions are working in different ways.

Upon making a circuit found on the third screenshot, I found that Sticky Pistons move differently when facing different directions. As can be seen, the circuit is a combination of four T-flip-flop circuits (on the first and second screenshot) and should make each Piston move simultaneously. However, as seen on the fourth screenshot, pressing the button in the middle didn’t make the Pistons facing North and South work. The Redstone circuits are identical, so it’s probably not a problem about the way I combined them.

Steps to Reproduce:
1. Create a T-flip-flop circuit and combine four of them, placing a button on the top of the center block.
2. Press the button.