It is rare when the VA severs Service Connection, unless it was granted in error.
The VA can make revisions of decisions under the following statue:
You still have "due process" rights to request a hearing if the VA proposes this decision.
38 CFR § 3.105 - Revision of decisions
www.law.cornell.edu
(d) Severance of service connection. Subject to the limitations contained in
§§ 3.114 and 3.957, service connection will be severed only where evidence establishes that it is clearly and unmistakably erroneous (the burden of proof being upon the Government). (Where service connection is severed because of a change in or interpretation of a law or Department of Veterans Affairs issue, the provisions of
§ 3.114 are for application.) A change in diagnosis may be accepted as a basis for severance action if the examining physician or physicians or other proper medical
authority certifies that, in the light of all accumulated evidence, the diagnosis on which service connection was predicated is clearly erroneous. This certification must be accompanied by a summary of the facts, findings, and reasons supporting the conclusion. When severance of service connection is considered warranted, a rating proposing severance will be prepared setting forth all material facts and reasons. The
claimant will be notified at his or her latest address of record of the contemplated action and furnished detailed reasons therefor and will be given 60 days for the presentation of additional evidence to show that service connection should be maintained. Unless otherwise provided in
paragraph (i) of this section, if additional evidence is not received within that period, final rating action will be taken and the award will be reduced or discontinued, if in order, effective the last day of the month in which a 60-day period from the date of notice to the beneficiary of the final rating action expires.