When powering multiple pistons in a diagonal line (one connects to another with a honey or slime block) depending on the direction some or all get powered.
Look closely at the differences between the piston rows and you will see all sorts of funky behavior.
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Thank you for your report!
We're already tracking this issue at MC-11193, so I will resolve and link this ticket as a duplicate.
The order in which blocks update along a wire is locational in all cases and not restricted to pistons.
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