The reason the Gander operator was 'annoyed' in post 1 is that CPDLC is no longer required. Refer NavCanada AIC 30/15 replicated by UK and Iceland. The GOLD will be revised to include these changes. In addition there is a Gander NOTAM to say they now assign eastbound 30deg W freqs by CPDLC.
The Iceland AIC differs slightly to Canada:
This eliminates the RT requirements for data link equipped aircraft to communicate "Controller Pilot Data Link Communications (CPDLC)", next Control Area (CTA) / Flight Information Region (FIR), Track and "SELCAL code".
All we need to do now is eliminate HF SELCAL checks, which achieve absolutely nothing.