As always, I stand to be corrected, but I don't think there's as much concern as there once was on either side of the border when it comes to Canadian stations protecting the U.S (or Mexico).....and vice versa. Especially in cases where the stations involved are more than 1,000 miles apart. I think its safe to say that the CRTC's main priorities include ensuring that stations provide prescribed levels of Canadian programming content for Canadian audiences, along with allocating spectrum space in such a fashion as to serve as many demographic sectors as possible.CKLW seems to be having frequent pattern problems that are keeping them on day pattern 24/7. (The CRTC isn't focused on keeping the pattern out of the U.S. They may have slightly tweaked the night pattern but I can't find solid evidence). Texas should be in the null toward XEROK though
Case in point regarding the latter.... When CFZM took over the 50kw signal in Toronto at the time the local CBC outlet migrated to FM, IIRC there were 23 applicants. The CRTC subsequently determined that "50+" was the most underserved demo in the metro area, and assigned the license accordingly.