How long will it take to learn to play an alto sax?

ok so I am planning to learn to play an alto sax
I already played a trumpet for a year and i can now hit high Gs pretty well (the one right above the staff)
I am planning to practice atleast 45 mins a day
In two months (when school starts), how well do you think i will be able to play?
i already have strong lips (because of the trumpet), good breath support, and am determined to learn the sax