TL;DR
Service connection in effect 10+ years cannot be severed except for fraud or false records. Underlying connection becomes essentially permanent.
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The 10-year rule (service connection protection)
Under 38 CFR § 3.957, service connection that has been in effect for 10 years or more cannot be severed EXCEPT in cases of fraud or in cases where the original grant was based on a falsified record. The underlying service connection is essentially permanent after 10 years, even if the rating percentage can still change.
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