Based upon the information provided, I would suggest that you request a DoVA rate increase initially since the turn-around time is potentially much less than submittal of an official appeal via the DoVA Notice of Disagreement (NOD) process.
If the objective medical evidence within your service/VA treatment record showed improvement prior to the adjudication of the final DoVA rating, then an individual shall receive a decreased final rating.
If I may ask, when were you officially awarded SSA SSDI compensation? Was your award of SSA SSDI compensation prior to the official award of your DoVA final rating? Moreover, what was the SSA SSDI award based on as the primary diagnosis and secondary diagnosis? What did SSA DDS state were the medically determinable impairments and its severity?
With that all said, you will need to overwhelmingly prove via objective medical evidence and/or documentation that your “Menieres” disease medical condition meets the VASRD criteria which you seek whether by DoVA rate increase request or official DoVA appeal process.
Thus, I quite often comment that "possessing well-informed knowledge is truly a powerful equalizer."
Best Wishes!
I have not had any appointments or more treatment prior to or since the final adjudication of the final DoVA rating. I was officially awarded SSDI prior to the final DoVA rating which was based on Meniere's.
In my opinion, one possible senario is as follows...
Unfortunately, it seems that the DoVA potentially viewed your non-continuation of appointments and/or treatments as an improvement in the severity of your meniere's disease/syndrome since the adjudication of your final DoVA rating.
Moreover, there seems to not exist any continuation of objective medical evidence and/or documentation within your VA/service treatment record prior to the adjudication of the final DoVA rating to support the "hearing impairment with attacks of vertigo and cerebellar gait occurring more than once weekly, with or without tinnitus" VASRD criteria for a 100% rating.
Therefore, the DoVA potentially lowered their evaluation in support of the "hearing impairment with vertigo less than once a month, with or without tinnitus" VASRD criteria for a 30% rating due to the lack of supportive objective medical evidence and/or documentation.
But, the encouraging news is that your Meniere's based award of SSA SSDI compensation occurred during the finalization period of your DoVA rating and can potentially be viewed as new evidence for either a VARR request submittal (while still on Active Duty) or a DoVA NOD appeal (as a military veteran).
To that extent, it’s in your best interest to also submit any new objective medical evidence and/or documentation procured (after receipt of your DoVA proposed rating) supporting the VASRD criteria’s 100% rating.
Thus, I quite often comment that "possessing well-informed knowledge is truly a powerful equalizer."
Best Wishes!