You are flying the A320. So you do not want to retire as an airline captain? Why do you want to go into management? The money? Think about what you are trying to do and decide exactly what your goals are. You sound very young. Maybe you should just stick with what you are doing until you get older and maybe you can save yourself a lot of hard work. I was very happy retiring as a major airline captain and in my opinion the worst job would be sitting in an office while the pilots are having all the fun. You have to decide for yourself though.
I love this reply by bubbers!!!
On ,that note, maybe you have loads of time on your hands whilst between rotas. Do something in your spare time, maybe, learn the guitar, piano, form a band, or get laid often with a partner of your choice. Go on an exotic holiday, or indeed do a degree of your choice, part time, spare time like, Computer Science. . . or something, indeed, something close to your heart.
All the advice on these posts is friendly and good.
Read bubbers post again though, its cool.