If my memory serves me correctly, there is no occupancy requirement to assume a VA loan. The purchaser does not have to be a veteran and does not have to occupy the home. The purchaser must be deemed creditworthy.
The Veteran selling the home can get a release of liability, but the Veteran’s entitlement that was used in purchasing the home is not restored unless the buyer assuming the loan is an eligible Veteran and willing to substitute their entitlement. In this case the Veteran assuming the loan must occupy the property for the Veteran selling the home to have their eligibility restored.
If the Veteran seller does not have their entitlement restored it could mean they have no entitlement, or not enough entitlement to use their VA benefits to obtain another VA loan. There are exceptions to this and the rules are complicated so the Veteran should contact a knowledgeable VA lender if they have questions about restoration of eligibility.