Time to obtain Class A rating

IM 1420 rated player.Im 14 how fast can i get to 1900? If i work hard in 1,2,3,4 years?

I've gained almost 900 in six months. Granted, my first rating was only 694, as I went 0-4 in my first tournament, so I did start extremely underated, but with hard work you can improve. I'm planning on studying a lot over the summer and am hoping to break 1800 within a few months. The most important thing you can do to gain rating points is to go to big tournaments and play up, for example I played U1900 in the chicago open despite having a 1500 ish rating, and a supplement of 1339 (I could have played U1500). I went 3/7 and will probably gain a ton of rating points, just because I drew a few 1800 players (+1 -2 =4)

I'd say you can do it in about 6 months with a regular study/play schedule. Like eight to ten hours a day studying and 2 hours playing on weekdays, four hours of study on saturday with six hours of playing, and taking sundays off.

Couple of years - depends on your talent, dedication and quality of training