Downgrade to 6.34.6 from 6.35 for hAP AC

I have an hAP AC currently running rOS 6.35 with firmware 3.31. I would like to install rOS 6.34.6 so that all my devices have the same rOS version. What is the procedure for doing this? When I place the .npk package in the Files list, the log states on reboot “omitting package routeros-mipsbe-6.34.6: newer package routeros-mipsbe-6.35 is already installed”.

Put 6.34 npk in the Files and then System/Packages/Downgrade

Excellent, thank you.