There was a separate thread to segregate out specific arising disruption but that has been silently locked so I guess here is the place:-
RE the Hayes disruption.
All trains were safely evacuated within a couple hours being stranded; it was evident very quickly that it was not going to be possible to restore traction power so efforts were the focussed on getting staff to trains to facilitate controlled evacuations of stranded trains - 6 in total (1 HEx, 3x GWR, 2x EL).
OLE damage affects all 4 lines. Down Main and Up Relief are in the process of being cleared of debris so that diesel traction can operate; but even when that is achieved there are 2x Crossrail units (Ex 9P23 and 9P25) blocking the dead section of the Up Relief which will need rescuing by locomotive. There is a loco on hand to achieve this at Paddington. There's also a Heathrow Express straddling the Down Main/Down Airport at Airport Junction; again without power due to isolated OLE sections.
The damage to OLE is however severe, so I would guesstimate no electric services in the affected sections for the remainder of the day; and a limited service likely tomorrow as it will need to be off for repairs to be afffected.
RE the Datchet disruption.
It had been planned, albeit not publicised (possibly intentionally) to close the railway at Datchet Level Crossings for a relatively short period of time to allow the procession from London to Windsor Castle to cross the railway at Datchet. The procession ran late; but BTP still took the closure of the railway on time. As such the line ended up closed rather longer than anticipated, with a ~40 minute pause in services between Staines and Windsor. This was then compounded as the train at the head of the queue at Staines couldn't be moved out the way as the crew only signed towards Windsor, not Egham so the train couldn't be diverted elsewhere to let the Readings stacking up behind through.