Bear in mind that the organisation of passenger rail services is in something of a state of flux at present, mainly but not entirely* as a consequence of the covid-related collapse of passenger numbers especially on commuter services. The business model of the previous TOCs (Train Operating Companies) has been wiped out, and it's far from clear just what the network or organisation will look like in a few years time.
(*There had already been concerns over the TOC franchising system, and it was under review even before Covid affected the travel sector so severely.)