I deal with this question on a regular basis and you are covered with a signed CF100 (as mentioned above) - however there is no guarantee the international medical provider will accept the Blue Cross card (even here in the US with our CAF dependants, for the most part if a provider sees a Canadian address with their PSHCP coverage, they won't take the insurance). Keep that phone number and contact info handy for the billing departments as there are a lot of "blue cross's" out there - we deal with Medavie Blue Cross, not Blue Cross International (based out of Florida and sometimes get CAF medical bills). In addition to the CAF Blue Cross card, there is another info card floating around out there - likely at your base clinic's blue cross desk. I know I have a few in my office and they tell you what you should do and numbers to call. There have been certain countries that may not recognize an out of country insurance company and people end up going out of pocket. If that ever happens - keep the receipts and then seek reimbursement through the clinic afterwards. If you don't have enough room on your credit card - make sure you have the phone number of your unit Duty O handy to ask for an emergency cash advance!
Finally, be kind to your medical file and ensure any clinical documentation that is generated comes back to Canada with you so it can be added to your file.