In version 6.1 getPossibleMovements use PipeTransport.outputOpen function instead of Pipe.outputOpen:
//if (container.pipe.outputOpen(o) && canReceivePipeObjects(o, item)) {
if (outputOpen(o) && canReceivePipeObjects(o, item)) {

But some pipe classes redefines Pipe.outputOpen to use logic.outputOpen.

PipeItemsIron.java:

@OverRide
public boolean outputOpen(ForgeDirection to) {
return super.outputOpen(to) && logic.outputOpen(to);
}

That is in version 6.1 logic.outputOpen isn't called and iron pipes doesn't work.

It is necessary or correct logic of call outputOpen func or for an iron pipe create the heir PipeTransport class

Confirmed.