If you use a planer on an end grain cutting board, be aware that very, very bad things are possible. Not only the destruction of your work, but your planer, house, yourself… It’s tricky business. Take 64th passes. Use sharp knives, if possible. Never ever stand in front of the infeed or outfeed tables. Basically, avoid it altogether if you’re not as lazy as I am. I know I and others have been successful with it, but some haven’t and with great distress. Use caution.
That being said, using the planer gave me a nice, flat board that I was unable to achieve with sanding alone. A drum sander will give you the same flatness without the safety concerns. I don’t own one, unfortunately.
Losing fingers since 1969