It appears they made the wording intentionally vague.
The Canadian service bulletin (posted here) provides more details. VIN ranges (or in the case of MY2017, the entire production run), and more specifics about the effects of the dilution (not just DTCs) and states one of the effects of the 'fix' is that "When operating the heater, customers may notice increased temperatures at the vents during the engine warm-up period.""Under certain circumstances, the vehicle may experience driveability concerns, which may result in DTC's" [emphasis mine]
No VIN range published, no mention of what the circumstances are, no mention of what the driveability concerns are, no clarification on whether the DTCs have to be set to qualify for the repair, or if the affected vehicles are just prone to setting those DTCs if the repair isn't done.
Going to make it tough on consumers with dealers that balk at doing the work. Hopefully we just get a campaign notification and once notified the dealer has to do the service.
The Canadian service bulletin number is A-9-18. It also specifies their warranty extension, which is apparently in a different service bulletin: A-10-18.
View attachment 126391
Also, in the US TSB, the part number for the "Auto Air Conditioner CPU Assembly" is listed as 79600-TLA-A62. It used to be 79600-TLA-A61, which I guess makes sense.