A number of delays (and for different reasons) have occurred, they were originally meant to start entering service in summer 2019, with all units in service by Dec 2020.
As far as I'm aware they've still not handed a unit over to swr yet, let alone begun any crew training. If I had to guess - and this is a rough guess I might add, I'd say they could possibly push one or two to take pax in September-ish, but even as I write that it sounds optimistic. Almost certainly that will be on the Reading line first anyway.