And yet on departure, instructing to climb FL170 does not cancel a 6000' altitude restriction unless we include 'now' or 'sid cancelled'.
But it does almost everywhere other than UK... Similarly if issued a STAR and told When Ready Descend to FL210 (and the STAR has say reach A080 by 20DME) and then you later clear the a/c to FL150... do you need to reissue the STAR or imply it still implies.... Can of worms really...