"... 27. Mr. Hancock [for the party seeking the extension] ... accepts, and indeed asserts that his case can be viewed at its highest if one focuses solely on the existence of the 21 day period under the Practice Direction-Arbitration, and treats the essential issue as being whether discretion should have been exercised in his client's favour underCPR 3.1 (2)(a) ... This is a focus which would, of course, arise only if one of various other conditions were satisfied: one being thatCPR 7.5 is inapplicable to a Part 8 claim form of the present nature; a second being that, althoughCPR 7.5 is applicable, it is for some reason right to ignore it when deciding heather or not now to permit an extension ... ; and the third being that, althoughCPR 7.5 is applicable, the owners could avoid its impact either underCPR 7.6 (3) or, possibly, underCPR 6.9 (1). In view of the conclusions to which I have ultimately come on the issue of discretion, I think that it is unnecessary to decide whether any of these conditions would be apply. However, since my grant of permission to appeal was influenced by the view that the judge may have been wrong to conclude thatCPR 7.5 operated concurrently with the Practice Direction - Arbitration, paragraph 27.2, I would confirm that I remain very doubtful about the correctness of the judge's conclusion that the two can operate cumulatively. Both were expressed to deal with a period for service of a claim form. It seems to me that paragraph 27.2 of the Practice Direction - Arbitration does on its face, and in this particular context, replaceCPR 7.5 . Part 49(1) of CPR provides: "