Can international DATA roaming be turned off by Xfinity?

I know how to turn off Data Roaming on my device (iPhone), but can Xfinity block DATA roaming on my lines in their system?  I do not want to deactivate international calls/texts, only DATA.

We travel internationally several times a year, and although I always keep "Data Roaming" turned Off on our iPhones, I want to ensure that no data roaming charges slip through.

This was never an issue for the past several years, but on our past couple of trips this year I noticed multiple data roaming incidents of .01-.03/MB each even though Data Roaming was turned off on my iPhones.  Luckily the $ charges were very small, but it was disconcerting seeing any data roaming charges at all.

I am completely satisfied using "Pay as you Go" for call/text roaming, so have no interest in subscribing to or paying for "Global Travel Pass" for data, especially now that XM includes international calls/texts roaming at no charge on all their plans.

So if I request it, can Xfinity block DATA roaming on my lines while still allowing calls/texts?