Except as provided in subdivision (b) of Section 391.3, when
a motion pursuant to Section 391.1 is filed prior to trial the
litigation is stayed, and the moving defendant need not plead, until
10 days after the motion shall have been denied, or if granted, until
10 days after the required security has been furnished and the
moving defendant given written notice thereof. When a motion pursuant
to Section 391.1 is made at any time thereafter, the litigation
shall be stayed for such period after the denial of the motion or the
furnishing of the required security as the court shall determine.