This modification to Law 26B was received after publication.

Law 26B now reads:

When an offending player's call is withdrawn and it is not replaced by a comparable call, if he becomes a defender declarer may, at the offender's partner's first turn to lead (which may be the opening lead) prohibit offender's partner from leading any (one) suit which has not been specified in the legal auction by the offender. Such prohibition continues for as long as the offender's partner retains the lead.

Please make a permanent change in your new law book. Remove 26B1 and the preceeding either and the following number 2.