I'm currently in 3rd year and long story short, even if I take 5 courses a semester each term until end of 4th year I will be 12 credits short.

How would you reccomend I take the extra courses so I can graduate on time?

(ie. Take extra courses during the fall/winter terms OR take 4 courses during the summer to catch up)

:/

Summer hands down

Summer for sure. The more courses you have, the harder it will be to do well. Better to graduate late with better grades than "on time" with mediocre ones.

Depends on you. When I was in a similar situation, I overloaded and I don't regret it.