^That is quite possible actually. But still, everyone plateaus in different spots. Some people I know did cruise right through the 1800s and only started hitting a plateau later. But yes, it gets harder with every class
The road isnt linear. You will have progress, then a plateau, then progress again, and .......I guess that 1100 to 1800 is happening when getting a good understanding and quitting blundering. What the next steps is about I can not tell, because I am not there yet (the 2000 I meet is a lot more experienced than me and has a deeper understanding, I think houndreds of otb-games does a lot). The difficult part is when you feel you are meeting the wall after a huge improvement. That wall stops many players, but if you keep on hammering it will sooner or later crack. My nephew Ola(that is exactly your age)met that wall at the age of ten. He was going for the child Norwegian championship and didnt make it. He was a favourite, but lost two very long, hard and close games. He quit chess and chose football and longboard in stead. A friend of him, Aryan Tari kept on playing , and have been maybe the most active Norwegian this decade. Aryan is 2535 Fide now and GM. He has played 1340 rated otb longchessgames, and that is really a big job done by a 16 year old.
^That is quite possible actually. But still, everyone plateaus in different spots. Some people I know did cruise right through the 1800s and only started hitting a plateau later. But yes, it gets harder with every class