What is "zurwandad"

Zurwandad or Zurvandad, was a Sasanian nobleman from the House of Suren who served as a herbad. He was the eldest son of the powerful grand vizier Mihr Narseh, and had two brothers named Kardar and Mahgushnasp. His name means "given by Zurvan". However, bearing that name does not imply that a person was a Zurvanist. However, Zurwandad's father was a Zurvanist, meaning that Zurwandad himself was also probably a Zurvanist. During the reign of king Peroz I, Zurvanism was declared illegal and was shunned from the Zoroastrian society. Zurwandad may be the same person mentioned in the Vendidad who had disputed Ahura Mazda as the supreme god of Zoroastrianism. Nothing more is known about Zurwandad.