Mostly we try to avoid arriving too early, as yes HD says, we get bounced off to the "stack" holding pattern. Terribly frustrating for us, but all in the campaign for peace and quiet on the approach path and airport surrounds, we like to keep the nimbys happy.
We do try to stick to our flight plan timings, (not knowing the guru's in ATC how they coordinate and juggle our slots lol) but occassionally a few of us arrive a tad early and have to hold (both planned holds and non-planned busy period holds). Some company procedures do not allow night landings (in or out of quota) so the donkeys are reined in and we try to slow down to arrive at a more suitable and coordinatable (new word) time..... if we cant slow down and help ATC out, then we accept the free tour of the London locale countryside for a few minutes or so....