Subject to the provisions contained in rule 10A and 10B, the sittings of a Board, Court, Labour Court, Tribunal or National Tribunal or of an Arbitrator shall be held at such times and places as the Chairman or the Presiding Officer or the Arbitrator, as the case may be, may fix and the Chairman, Presiding Officer or Arbitrator, as the case may be, shall inform the parties of the same in such manner as he thinks fit.