As we're flying the route next week I have been checking the punctuality of the SIN departures and BA15 seems to be leaving about an hour late every day recently, which means a take-off anywhere up to 2300h BA11, however, seems to be getting away much more punctually. Is there a reason for this, perhaps a late inbound of the 777? Strangely the EF reliability data show the later flight as being much more punctual but it certainly hasn't been the case recently.