I think if the parties had agreed to block the diary of the principal author there would also be a more specific timing.
We do actually know the approximate rates from City v PL
- The Club made two submissions in this regard:
...
ii) the fees that were paid to the arbitrators in this case were "far from derisory": in a case in which the standard rates were applied the chair received £1,500 per day and the wing members £750 per day and in this case the parties agreed that the members each received £450 per hour.