Q&A - Experience Required to get a Commercial Driver's Licence?

... however, in order to be able to apply for a Class 1,2,3, or 4 BC license you first must hold a Class 5 BC license and be at least 19 years of age.

So for instance, a person might have exited GLP (Class 7) by taking their Class 5 Road Test first thing in the morning, passing it, and then immediately applying for the Learner License for one of those four professional classes (knowledge test, roadsign test, fundamental medical & eyesight checks).  At that point in time - and it could be the same day - provided they had the necessary vehicle to take the test in, and the licensing office were able to provide an appointment with a Driver Examiner that same day, then if they were also able to pass the practical Road Test for that class of license their goal would have been achieved.

I'm not sure if anybody has ever 'jumped through the hoops' so rapidly - but if you did (having miraculously learned how to drive a taxi, dump truck, bus, or semi-trailer truck competently, and could immediately provide it) then their goal of obtaining a commercial license would have been accomplished; a provisional license would be issued, contingent on a more thorough medical check being successfully completed and submitted within 30 days.

Hope this helps; you'll find more thorough and complete information on the ICBC website, Getting Your Commercial Driver's Licence.