You cannot switch from a higher-numbered build of Windows 10 to a lower numbered build without a clean install. Since the Dev Channel are all higher-numbered builds that the Beta Channel, a clean-install is the only way to immediately leave the Dev Channel.
You can switch which Channel you are in, but since you already have a higher-numbered build, you will not see any new Windows builds offered. Your Dev Channel build is quite likely to expire before the Beta Channel ever gets to a higher-numbered build.
If you feel that the current Dev Channel build is stable enough for your needs, you could switch Channels just to prevent constant Windows build updates for a while.