Interaction between Dokkan and Hidden Potential

What happens when you Dokkan Awaken a unit with + stats in hidden potential?

Do they get added to the unit after the Dokkan Awaken and are now part of the base stats and hidden potential resets or does the hidden potential stay because you can only do it once or does the hidden potential stats go away and start over?

I'm asking because I do not want to spend my hidden potential orbs on a unit if those stats are taken away, but I also need to know if I should max out my hidden potential now or wait until the unit is fully awoken.