if you want elite classes, request privates or talk to your instructor about having elite classes, until then, jiu jitsu will continue being all inclusive. when you pay your gym dues, you pay for the use of all of the classes even if you don't go to them, so those noobs paid just as much as you to be there
another way to look at it is, you don't have to train with them, you GET to train with them. as a noob myself, i remember the guys that help me grow, and probably always will. you are going to be part of their progression.
Why cant you just continue to train with the same guys you have been and just do your thing like normal, with a few extra new guys in the class? If it is because of the starting/stopping to teach and the level of the technique, then that is on your instructor. with 12 guys in a class, you good coach should be able to scale and escalate things so that both black belts and white belts get a quality practice, especially when blacks go with blacks and whites go with whites.
if you want elite classes, request privates or talk to your instructor about having elite classes, until then, jiu jitsu will continue being all inclusive.
However, my head instructor is notorious for being very slow and forgetful about promotions. So do with that what you will.
Clearly you should buy yourself a blue belt, hand it to your instructor, and be like "I think you forgot to give me this 6 months ago."
But really, training with "noobs" is normally the high of my nights training. I may not get a competitive roll in, but I'll be able to better understand positions and moves more thoroughly because I'm able then to think while rolling whereas when rolling with higher belts, I'm not allowed that luxury of thinking and have to flow with the go. On the other, it all depends on the training session and some need to be for the more advanced players rather than the fresh on the mat noob who'll try a kimura in your guard. (I'm sure we all tried this before and got our back taken -.-)