Section 52F. The board may, without a hearing, suspend or refuse to renew a registrant’s license if the board finds that the health, safety or welfare of the public warrants such summary action; provided, however, that the board shall, within seven days of such summary action, afford the registrant the opportunity of a hearing pursuant to chapter thirty A. Any suspension imposed by the board shall remain in effect until the conclusion of the proceedings including judicial review thereof, unless sooner dissolved by a court of competent jurisdiction or withdrawn by the board.