I'm not sure what you mean by an ideal timeline. Generally speaking, it's next to impossible to find an employer willing to go through the LMIA process. The process is long (typically 4-6 months), expensive and has no guarantee of approval. If you haven't started your program yet - definitely change schools. Studying at a school that doesn't get you a PGWP is a waste of time and money and effectively gives you no path to working after you've completed your studies (or qualifying for PR if that's your goal).