Expectation (behavior in 3.0): ingots will be pressed by mechanical press on mechanical belt one by one. One does not pass through until it is processed
Actual behavior (in 3.1): after 1 ingot is pressed, the mechanical press retract, the next ingot simply pass through and does not stop at the mechanical press to be processed.
Step to reproduce: simply drop several ingots on mechanical belt with mechanical press

Same problem. I changed the belt and press speeds and it got worse, now it skips the next 2 before pressing again, even if i slow it down.

Ok, the behavior of the process has changed.

• Before -> The processed item/stack stays "under" the press until it pulled back and get transported after.
• Now -> The processed item/stack get transported while the press is pulled back and the next item/stack moved along.

So the processed items get moved to early!

I searched for a code changes that explains this new behavior ... i guess here it is. So before the reference of TransportedItemStack gets overwritten! And now its a new instance of TransportedResult. The reference hold by the press instance is NOT the new TransportedResult its still the TransportedItemStack, if it's removed/deleted, the press can't "HOLD" it ... like i said, i'm guessing :D

Same problem. I changed the belt and press speeds and it got worse, now it skips the next 2 before pressing again, even if i slow it down.

Ok, the behavior of the process has changed.

• Before -> The processed item/stack stays "under" the press until it pulled back and get transported after.
• Now -> The processed item/stack get transported while the press is pulled back and the next item/stack moved along.

So the processed items get moved to early!

I searched for a code changes that explains this new behavior ... i guess here it is. So before the reference of TransportedItemStack gets overwritten! And now its a new instance of TransportedResult. The reference hold by the press instance is NOT the new TransportedResult its still the TransportedItemStack, if it's removed/deleted, the press can't "HOLD" it ... like i said, i'm guessing :D

They didn't mention it so i assume it's a bug

@stop-x13 There is a fix in e92e9a7 and it will press one sheet at time from a stack on belts, unless you config bulk pressing for stacks to sheets.
thx @simibubi the commit can close this ticket

Addressed in 0.3.1c, thanks for reporting!