The first big question I have is this. 99003 worked 4L68 on 03/09/26 (Thursday) and got heavily delayed. 4M68/4L68 on 04/09/26 (Friday) was then cancelled. The next working I have for 99003 is Peterborough - Leicester on 11/09/26! So does anyone know please how 99003 got from London Gateway to Peterborough and when, as I haven't been able to find anything!
There's a mention in TRUST of the already late 4L68 on 03/09 getting a plastic bag wrapped around the pantograph between Grays and Tilbury (changed to diesel mode and lost 5 minutes).
Looking in TRUST for a direct service from London Gateway to Peterborough Yard, the only regular weekday move that comes up is 4E00 which is booked to recess there for an hour (4E08 and 4E19 are just crew relief in the station).
I think 99003 most likely moved to Peterborough either on Friday's 4E00 (04/09), or possibly remained at London Gateway for a couple of days and moved to Peterborough on Sunday evening's 4E08 (which terminates there). Either move would have occured either too early or too late in the day to have a good chance of being photographed.
Given the relatively short time between 4L68/03 arriving and 4E00/04 departing, plus the possibility of plastic wrapped around the pantograph, I think a movement on Sunday's evening's 4E08 might have been more likely, as it may have taken a little while for a decision to be made as to what to do with the loco and where it needed moving to.
TOPS isn't very helpful because it shows 99003 being retrospectively teleported to Peterborough on 4L39 from Wakefield on 10/09.