I hope southeastern get the same trains as greater Anglia class 720 and south western railway class 701
720's are an absolute no no due to then being too long, as for the 701's maybe but also rather unlikely given how much trouble Swr are having with their ones. The Swr 701's were meant to enter service in late 2019, it's mid 2023 now and AFAIK they haven't even started their driver training runs.
Right now Swr are saying that they want to have the first 701's in service by Christmas but because so many dates have been set and missed all ready, it would be of little surprise to anyone if this new date is missed as well.
It has been years, as I said in an earlier post, the Swr 701's were originally meant to enter service nearly 4 years ago now.
Derby haven't covered themselves in glory. There were serious issues with the 710 and 720s both still being introduced more than 3 years late. The 345s also had issues but due to them using an older operating system they weren't too late entering service. The 720s are nice to travel on, though in retrospect and with the benefit of hindsight, the number of seats is just stupid.