You may now request another hearing before the Board of Veteran Appeals when you case is remanded! Cook v. Shulkin
The old case said there was but one administrative review by the Secretary which meant upon a remand either to the BVA or the Regional Office, you did not get another hearing to testify or submit evidence at a hearing.
Under Cook, there is no limit the number of BVA hearings a Veteran may have after a remand.
Cases go up and down from the Board to the Court, Remanded back to the Board and sometimes remanded back to the Regional Office. On each remand the Veteran is entitled to another hearing.
However, if you really don't need another hearing don't ask for it. Another hearing adds another 12 to 18 months onto the claim before a decision.