Hello guys

I Have been using the 4axis tb6560 board since a long time now without any issues at all
The board components barely gets warm even after a long time of use
Never skipped a single step on any stepper motor
Steppers also never get hot whatsoever
I am only using slow rpm and the lowest amp setting (1/4)

Currently using a dual Y axis setup, so I am using all the 4 axis ports on the board
I was thinking to have a rotary A axis
So I need to free up an Axis port for that

Can I simply use one port to drive the Y dual motor Axis (wire in parallel) to free up a port?
based on the above machine situation would I just raise the max amp of that axis to 1/2 instead of 1/4?
Anything else?
What kind of problems I might face for doing that?

Thanks