I could be wrong but I thought OK stopped all flights to the US (except maybe JFK which was due to stop as well?).

I think you should call CSA and specifically ask them to check KLM and Air France for flights. You can also request Delta. All airlines are part of SkyTeam and your SkyTeam miles (I'm assuming through CSA) should get you a ticket. Maybe no "low award milage" tickets are available for the dates you're looking for.

Your other option is to call KLM, Air France or Delta directly, ask them for award availability and figure out specific flights, dates and times. Call CSA back and tell them you know there's availability and you'd like to book the ticket with your CSA miles. They should be able to do this for you.

Maybe someone with more specific experience booking with CSA miles will also reply. But booking in December for next year is definitely not too late.

-RM