Continuances may be granted by the board prior to and during hearings conducted under provisions of this chapter, either on its own motion or on petition of the subject of the hearing, provided that such petition is sent to the board in writing immediately upon receipt of the hearing notice and that it specifies the reasons for continuance. Continuances requested during the hearing may be granted by the board panel if it appears in the public interest or in the interest of justice that further testimony or argument should be received.