As others have said, contact the AFM. Based on my experiences and past approach, I recommend that you state that it is a stocked trout section with wild trout in high numbers. Do not state that it IS a Class A equivalent, as that kind of firm statement based on a fishing rod assessment has a good chance of ruining your credibility. A better way to say that is that it fishes like some other Class A’s that you fish, most similarly to x, y, or z stream with which the AFM may also familiar. If your long time experience with the stream, if you have had such experience, such as 10 yrs, tells you that the wild trout population has apparently improved very substantially, that will be worth mentioning as well. Don’t stretch the truth. If a crew spends the time and $ to go out there and the population isn’t even close to what you represented, your cred will be lost.
Sampling schedules are already set for the year, based on the past, but reporting it now wouldn’t hurt as on occasion I found time while in a given geographical area to take a look at a water that had not been on the schedule that year. It certainly doesn’t hurt to discuss the stream with the regional AFM now. Finding Class A’s was a stated priority for the staff the year that I retired (2019) and it would not surprise me if that is still the case.