Shouldnt take much more than 4 weeks at 5 days a week for even a slower learner, when i did mine i had it done in 3 and so did the guys i was doing it with. Mind you this is if you do your IREX prior to the course.
Are the courses you heard taking 3 months including the IREX study and exam? If so it still seems excessive by at least 4weeks if it is in fact full time.