Questions about adding a 1 Year Free Unlimited Xfinity Mobile Line to an existing 5 Year $50/mo. - 1 Gig Internet Price Guarantee

I see an offer about claiming an Unlimited Xfinity Mobile line for 1 year, free of charge.  It appears the $25 line activation fee is being waived until 3/23/26.  I have several questions regarding this offer.

Is the 1 year of Unlimited Xfinity Mobile truly free?  No cost?  No charge for gov't taxes, sales tax, 911 fee, USF fee, FCC fee, Operational Compliance fee or any other surcharges/fees for 1 year?  I see there is a Premium Unlimited line for $10/mo., but I am referring to the Standard Unlimited line offered as Free for 1 year.

If I add an Xfinity Mobile line to my current Internet only package: 5 Year $50/mo. - 1 Gig Internet speed Price Guarantee - does that in any manner affect my current Internet pricing deal guarantee?  Whether it be price, term, internet speed, wireless gateway or any other item not mentioned?  i.e. would I lose access to the $50/mo. 5 year price guarantee for 1 Gig internet speed?

If I decide to remove Xfinity Mobile service from my account in 1 month, 1 year or 2 years, etc. - does that in any manner affect my current Internet pricing deal guarantee?  Whether it be price, term, internet speed, wireless gateway or other item not mentioned?  My current Internet only package: 5 Year $50/mo. - 1 Gig Internet speed Price Guarantee.  i.e. would I lose access to the $50/mo. 5 year price guarantee for 1 Gig internet speed?

If I decide to remove Xfinity Mobile service from my account in 1 month, 1 year or 2 years, etc. - is there any cancellation fee or any other monetary charge?  In this scenario I would still be an Xfinity Internet customer.

The gist of my inquiry is if adding or removing an Xfinity Mobile line will at all affect my current Internet price, term & speed guarantee? Or somehow negate the deal.  Also if the 1 year Unlimited line is truly free (with no hidden fees/taxes/costs)?