I can't see that you have any dispatch pattern, so this is a classic case where the tracking works against you. If tracking says delivered and it is after the estimated dlivery date you get a Late Delivery.
You need a standard pattern of dispatch, say 3 days but ensure you post after one day. That gives you two bonus days on top of ebays estimate.
Have you identified the items that are delivered late, if they are the same sort of thing, then you should investigate the cause. For example when do you you buy your labels? Are you losing days if they do not get to RM for 24 hours from the date purchase as time no doubt counts from Purchase and not actual posting.
