Borders, Citizenship and Immigration Bill [HL]

It must be clear to the Government by now that there is widespread concern about Clause 46 and the details of it. However, I should like to mention my experience of the last time that I flew to Belfast from London in November last year. I was asked to produce photo identity. Was this under some power or legislative authority or was it just overzealousness on the part of the airline? To ensure that Northern Ireland is not being discriminated against, what is the position—last year and this year—with regard to flights or trains to and from Scotland? Is photo identity required for such journeys?