5.  Motions

(a)  Any motion addressed to the jurisdiction of the Board shall be promptly filed. Hearing on the motion shall be afforded on application of either party. However, the Board may defer its decision on the motion pending hearing on both the merits and the motion. The Board shall have the right at any time and on its own initiative to raise the issue of its jurisdiction to proceed with a particular case, and shall do so by an appropriate order, affording the parties an opportunity to be heard thereon.

(b)  The Board may entertain and rule upon other appropriate motions.