I recently picked up the Baofeng mp31, and was messing around with chirp software. CHIRP doesn't work on them directly. but I found that the Baofeng T20 frs version will allow you to change and hold the settings to high power on channel 1-22 only and change to wideband as well. just read the radio and change settings in chirp, then write back to radio. I then used the software from Baofeng to read the MP31 and all settings stayed from the Chirp software channel 1-22 only sadly and the rest of the channels to 38 stayed listed as normal. not sure if it actually did any thing since I don't have a way to verify if it other than software indicates the changes.
I just wanted to share this information.