Calendar for the MAD training flights (Caveat Emptor, some changes may still occur)
EDIT: For 6th Aug. onwards:
Head for Points (HfP) has received some information from BA about the proposed dates and flights for the A350 training flights. The green calendar slots reflects only those that are CURRENTLY known to be A350 flights. (these may change for one or more reasons but this is what is planned or the seat map is now showing <3 days out at 11 AM> at least!) The 464/465 flights will be the main flights used to do the training and they are the last set of slots each day as these allow plenty of extra gate time in case of issues and also in case of any IRROPS (as they will then have plenty of time to do debriefings/modifications/changes or any other issues that come up and get it sorted in time for the next rotation. In addition to the evening rotation, BA has stated that some days they will also use the 456/457 run (first morning run) to use the A350 as well but has not published any dates, so it is truly a gamble and it may not repeat the week after so may be irregular, however, if you can't get on the evening rotation, try the first flights 456/457 and you may be lucky and get it then. The first morning rotation is the 8th Aug. (as previously planned) and I have added the 10th Aug. as the next 'likely' date the morning rotation is planned (according to the old schedule but this is not at all guaranteed so caveat emptor).
I have no direct connection to BA and therefore am not the source of the various schedule timings, please see the first post in this thread for the credit to those individuals. My contribution is simply to put the schedule into a calendar format and to facilitate any meet-ups FTers may wish to do when trying to arrange a flight on the A350 training flights.
Aug 2019:
The calendar is now at version 9 (above) and reflects the latest info from BA directly through third party websites news. I have removed the morning 456/457 runs from the calendar as BA went out of their way to say it would do some days using those flights but not stating when (and not stating it was regular each week either)...so only the above are currently planned (but may change as well still). The morning 456/457 runs were scheduled 3 x weekly in previous calendar versions but we'll wait to see what empirical data shows us before guessing if this remains true or if it is other dates/non-repeating days of the week, etc...BA has not mentioned any other flights though so if you want to try to fly the A350 on this route do pick the first or last BA flights on that day to have any chance of it happening. (note exceptions where no flights may occur in the calendar above). Seat maps are now starting to show the A350 3 days out.
For those people that have booked flights in Sept. it is now nearly certain that no training flights will occur in Sept. Please do not forget to cancel them or decide if you will fly them anyway, etc! I'm very sorry if you booked this previously and are now disappointed, however, you will realise that it was a risk and there were no guarantees it would occur. I hope you'll try to fly her on the Aug. schedule and get lucky.
I'll also start a list of who is going (and when) in the wiki for those that wish to publish their flights in this thread (or add it yourself to the wiki if you wish) to try and organise get togethers.