Just to check I am correct before I complain to East Midlands Railway. I was planning to travel from St.Pancras to Luton on Sunday, I held a Zone 1-6 travelcard on my oyster card and bought a super off peak return from Boundary Zone 6 to Luton at £8.50. Due to signalling problems south of the Thames, Thameslink services were disrupted so I planned to take an EMR service but was refused at the barrier "as that ticket is only valid downstairs" - presumably meaning Thameslink only, I had no joy in convincing the chap on the barriers otherwise. I went back to the ticket office who voided the Boundary - Luton ticket for me and sold me a London Terminals to Luton Super Off Peak for an additional £2.30. I missed the 0956 because of this and took the 1030 EMR which was the next train to Luton. Is my understanding correct that my ticket combination was valid?