How to turn off *21 (star21) forward all calls to voicemail

Hey all,

    I'm trying to figure out a way to set our night mode like we did on our old carrier. We would call forward the calls to last line in our hunt, which was set to 1 ring. For some reason, something happened on our install and we can't see our hunt in "My Account" and support tells me the lowest they can set the number of rings is 6. The other option we had with the old carrier, is they had a phone number that you could forward calls to, and (based on caller id) would send calls to our voicemail. If any one knows if comcast has something like that, that would be great. 

But I think my best option is something I found in the star code list
https://secure.xfinity.com/anon.comcastonline2/support/helpandsupport/businessclass/help_articles/CB_BVE_StarCodes_SLS90624_3.18.pdf

It lists *21 "Call Forwarding Always To Voice Mail". This feature works great and would be the answer, if only we had a way to TURN IT OFF reliably. #21 does nothing. I went through each combination of * code from 00 to 99 excluding ones i knew worked and none of them turned it off. I had to call support. They claim they did nothing to turn it off, but the calls stopped going directly to voicemail when they took a look. Please let me know if you know how to use the feature properly. Thanks! 

PS, while trying to open this I noticed that there is a difference between business voice(we have analog lines coming from modem so I assume this is what we  have)  and business voiceedge, which googling tells me is comcast voip phone system. The above star code list is for voiceedge, so perhaps there is a different list for voice, but that's the only comcast star code list i could find.