6 months...... If you are talking being an accomplished jazzer with the ability to improvise over anything I am going to say no way. Not to be negative, not to say don't go for it..... I am just being realistic.
I also do not know your ability. How well do you read and how is your jazz chord vocabulary right now?
I figure that with 6 months of intense study you may end up being able to fake your way through some jazz tunes but if you are going from minimal jazz knowledge now ......you will not be able to consider yourself a jazz player in 6 months and nor will any serious jazz musician consider you a jazz musician. That does not mean they will not take you under their wing and help you along.......experienced musicians tend to want to help dedicated up and comers......they see themselves in them.
A great attitude is a must though.
Somebody mentioned Kind Of Blue as if it were a benchmark or something. The album Kind Of Blue is very modal. The songs are either 12 bars or very modal, where one or two scales cover it.....so this is dead easy to solo over or take way outside....... there are hardly any changes to worry about.
By contrast.... tune's like Donna Lee, My Foolish Heart, 'Round Midnite, Molten Glass, On Green Dolphin St etc etc ad infinitum.........thousands of songs like them with complex chord changes and rhythmic structures.......what are you going to do when you sit in with a band and they call a difficult song you don't know? The way I think, is that if you cannot blow a cool solo over any changes in any song in any key at a variety of tempo's.......you are not a jazzman. You might be able to play
in the jazz style on a song or three....... but you are not a jazzman. Oh and reading......... serious jazz players expect you to read flyshit.
Like I said, I am not being a bummer....I just will never be one to want to blow smoke up your ass. I like your attitude and I think you should go for it because it will make you a way better player and besides, you may prove me totally wrong.
Consider this though..... a better approach perhaps. Why not concentrate on being a super jazz rhythm player in 6 months? This will include being able to read any chord chart and being able to play any jazz chord correctly, not only the standard voicing's everyone learns but having a nice handle on some hip voicing's. You should also be able to transpose on the fly. Maybe the big band plays Stella By Starlight in the key it was written but a singer sits in and asks if you can play it in a different key to what your charts are written in. Can you do that as you go? I watched the musicians in Blood, Sweat and Tears do that at a rehearsal-blew me away.
You should also learn all the substitution rules and be able to apply them on the fly, know all the key signatures by heart and be able to comp in any style authentically....... bebop, Latin, straight ahead........ in any time signature.
Here's what......... 3-4 months solid study you can do it as a rhythm guitarist.....get all the basic jazz grips down and be able to hold down the rhythm as you read charts.
Then.....if you can convince the big band to let you sit in on rhythm, you get your foot in the door. Pull off a few rehearsals and show them you are fun to work with and that you are super dedicated and genuinely happy to be where you are at and that you apply what they teach you.........this lays the groundwork for you working your way up. Then as you go along and you have learned to solo over a song or two you can ask to blow a solo at a rehearsal....if you pull it off you likely will be doing it at the next gig.
And so you move forward. Oh, and if they have a guitarist...... ask if you can sit in for no pay and do that as often as you can. Gig's, rehearsal's ....see if they will let you play as long as you stay out the way and do not slow rehearsals down 'cos you are blowing it.
To me this is a much more humble approach and is much more do-able. It also takes a lot of pressure off you to try and learn to be a jazzman in 6 months in terms of being a soloist, being able to improvise freely.
Remember......... band leaders do not like to be made to look bad. If they do not feel confident in you you will not get a shot, definitely not a second shot after you blow it with them. Come in lower...... ask to be the rhythm player and then keep your ears open and learn. The older experienced cats will likely mess with you a lot....if they do they are testing you, not your ability.......your tenacity, the ability to take a joke. If you pass that they likely will start teaching you the tricks of the trade. If they dick with you it is often a good sign.
Just my opinion....maybe you are a prodigy and end up a tough soloist in 6 months or so. ?
The book to get is
The Real Book which is a fake book of all the standards you will need to know. Then a
GREAT way to learn jazz is with the
Jamey Aebersold series. These are charts with a CD of the songs containing the accompaniment......piano, bass and drums....for you to blow the melody and solo over.
The main one you need to
suss out first is "
The II-V7-I Progression".
http://www.jazzbooks.com/mm5/merchant.mvc?Screen=PROD&Store_Code=JAJAZZ&Product_Code=V03DS&Category_Code=AEBPLA (Check out the audio examples)
Go for it dude and good luck with it.