"For accounts opened after 7/31/19, with By the Gig lines, a minimum $12.00 charge applies per month, regardless of data usage. Data charge applies to each GB or partial GB of shared data. Data shared monthly with other By the Gig lines. No rollover data."
Old accounts remain under the old rules so you can add new lines etc under the old rules.
There is also a $20 charge per month if you do not maintain another xfinity service (up from $10)
And a couple of new plan tiers:
3gb for $30
10gb for $60
This change makes it a good costly to maintain talk and text lines on Comcast, which I've been doing. Currently, I maintain 3 lines which are actually used by my parents in a city not serviced by Comcast and a 4th one as a personal backup. I pay only about $2.50 in taxes and fees for each line for unlimited talk and text. All phones have data turned off at all times, so I never get charged by the gig.
I generally use the 4th and 5th slots for going through 3-4 month activation/deactivation churn cycles to take advantage of Xfinity's iPhone BYOD promotions. This requires a port-in, and I've been using freedompop numbers for that. You also have to maintain an inventory of spare iPhones...I used to do this with a 5s and 5c but had to upgrade to iPhone 6. I've already earned $600 this year doing this. I made quite a bit more last year when the rebate was $150/line and my parent's lines were new.
It looks like with these changes, someone newly signing up for Xfinity Mobile will pay an extra $12 for what I do.
Xfinity Mobile early adopters will soon no longer be grandfathered. All users are being migrated to their "Second generation" plans, which require minimum payment of $12 (plus taxes) even if you don't use any data. Previously, you could just get away with just paying taxes with no monthly data charge if your account used less than 100mb in a billing cycle.