The ABS Apprentice title refers to those individuals who are dues paying members of the ABS, and are working their way towards JS status. The only requirements are that you pay your annual dues, remain in good standing with the organization, and are forging blades.
Its a wonderful journey to embark upon. You'll meet a lot of great people, and learn as much as you can take in. Sometimes it might seem like a road to nowhere, but the day they call your name at the ABS banquet, announcing your JS status (and hopefully later on your MS status) the journey will be more than worth the effort.
I began my journey in 1988, achieved my JS in 1994, and my MS in 2000. Little did I know at that time, that the journey had only just began.....since achieving my MS status, I have had the pleasure of teaching all over the U.S., Canada, and Europe, and have met so many talented and kind people, and found that in every instance I always learn something new and exciting. It may not be this way for everybody, but I have come to realize that this whole Bladesmithing thing isn't about making the perfect knife......it's all about the journey/quest to do so. I think if you keep that in mind, you'll never be sorry you headed down this trail.