Original booking Business Class with Air Canada R/T MCO/BKK with a return through Montreal. Need to change the return flight date and a different routing if possible. The original routing takes me BKK/NRT/YUL/MCO. I want to avoid Montreal as that is an overnight connection to MCO. I see that a few Air Canada routings go through LA, SFO, and Chicago to Orlando. Imagine they are code share flights with Thai, ANA, and United. Is this a probability or am I going to run into trouble?

Thanks Again