I have been using the CTRL shortcut for a while and now no longer use the "deployment" phase, but it always goes to the deployment phase at the start of the round. This always makes me regularly accidentally add units I didn't want during the beginning of the phase when I meant to move the current ones.

Is there a way I can change the default to go directly into attack/transfer phase?

Thank you

There is not, unfortunately. But you can use the "A" hotkey to move it from deploy to attack.