Accelerated programs (often 2-4 weeks) are intense "immersion" style courses. They are excellent for retention because you fly every day. Pros: Muscle Memory (you don't forget skills between lessons) and cost efficiency (less review time). Cons: Drinking from a firehose (grueling ground school) and weather delays (if it rains for 4 days, your schedule is blown). Search for "14-day PPL course" or "finish up PPL programs quickly".