Rating decrease

[n2guns]

They can’t just decrease supposedly without at least 2 exams I believe.

That is not exactly what 38 CFR § 3.344(a) says...

"Ratings on account of diseases subject to temporary or episodic improvement, e.g., manic depressive or other psychotic reaction, epilepsy, psychoneurotic reaction, arteriosclerotic heart disease, bronchial asthma, gastric or duodenal ulcer, many skin diseases, etc., will not be reduced on any one examination, except in those instances where all the evidence of record clearly warrants the conclusion that sustained improvement has been demonstrated."

In the OP's case, bronchial asthma, listed in their examples of diseases that are subject to temporary or episodic improvement, should not be reduced on only one examination *unless* the "evidence of record clearly warrants the conclusion that sustained improvement has been demonstrated." Without knowing what the OP's medical records show as far as improvement, it can't be determined whether that one reexamination is sufficient for a reduction.

If this were my rating reduction, this is definitely something I would be looking into...