If a student has successfully completed a course, e.g. A1, it is possible, with some special preparation, to take the A2 exam. If a student has successfully mastered B1, it is possible to try to pass B2 and so on. Of course, you should not do this if you want to learn to speak and understand.
But if you urgently need to confirm the level of the language and the deadline is very tight, then, in principle, it is possible. There have been several such cases over the last year.
Artyom is one of them. We were in the middle of B2. And then we needed a B2 certificate. We passed. We got to the middle of B2 and needed a C1 certificate in a month and a half. We added 1 lesson a week and passed the exam about a month after we started training.
Anything is possible when you have a clear goal and a desire to work....
It is important to note that even if you have passed the exam for a certain level and you continue learning the language, you should never jump through the levels. Go in order, slowly, but only forward!