I’ve had a reply to my letter about breaking an OSI by using a bus. The person answering the letter has not understood what I was trying to say, so I’ve sent back an email reply explaining it in a different way. At least this letter has been answered, unlike the earlier ones concerning the broken OSI at London Bridge.
And a reply arrives the same day to this followup email. They do understand what I’m saying, but there is no way to allow a bus to be used in the middle of a rail journey. At least we now know.