I'm not sure how NOW handles replacements, but the modem has a label saying "This is customer owned equipment and should not be collected or swapped by Comcast

I'm not sure how NOW handles replacements, but the modem has a label saying "This is customer owned equipment and should not be collected or swapped by Comcast personnel, unless within warranty repair." The FAQ says "your NOW Internet Gateway comes with a 90-day warranty" so perhaps they'd care somewhat about mods within the first 90 days.