Ice path and arctic beam cannot be cancelled individually since ability cancel change.

[noir]

as per title. Pressing cancel button cancels both abilities.

 

[Wesley Grey Talon]

You are correct with default keybinds. If you'd like a temporary(?) workaround you should be able to go to

1. keybinds
2. (checkbox at top) unit specific hotkeys and select kelvin
3. scroll down to "Change Cancel Ability Mode:"
4. "Ability Key" or "Cancel Key or the Ability Key

If you want the same functionality across all characters you can skip step 2. Just be aware you may have to adjust accordingly with other heroes channeled abilities.