Modem not provisioned for mid-split / enhanced upload (OFDMA disabled)

Greetings,

I recently replaced my modem with a Hitron CODA56 on an Xfinity plan that advertises ~300 Mbps upload (enhanced upload / mid-split).

The modem is online and working, but it is only bonding legacy upstream channels. OFDMA upstream remains disabled, and my upload speed is stuck around 60–80 Mbps.

I contacted Xfinity support twice (phone and chat). Both reps claimed they reprovisioned the modem and pushed a new bootfile, but there was no automatic reboot, no config change, and no speed increase, even after waiting several hours and manually rebooting the modem.

This appears to be a provisioning issue, not Wi-Fi or signal related. Signal levels are healthy, and downstream speeds are correct. Speed tests are performed directly from a UniFi gateway connected to the modem, no Wi-Fi or VPN involved.

I would like to ask for confirmation that my node supports mid-split, and for the correct mid-split / next-gen bootfile pushed to my modem.

There were also references to my previous two modems when the Xfinity assistant asked about my devices (the second rep said they could remove those, not sure if it happened). I’ve heard that can sometimes cause issues provisioning for next-gen if an older device is still showing anywhere on the account?

Happy to provide account/device details via Modmail.

Thanks!