I am a Japanese full-time student in the UK now on a trip to Paris.
I have two passports: one new and valid, one old and void. However, my student visa/Schengen visa is in the old passport, which I forgot at home in the UK. What is worse, I lost my debit card one day before the trip and so, I only have money in cash.
Now, I used the Eurostar to get from London to Paris. Surprisingly, I was not asked for my Schengen/student visa in my old passport throughout: my new passport did the job and I got to Paris without any issues. And so now I'm in Paris.
My worry is when I leave Paris to go to London, will I be in trouble? I asked the UK border personnel in London before my departure to Paris, explained to them, to which they replied "on our side, it won't be an issue since we can look you up on the system and confirm. But we don't know what the policies are with the French with a Japanese passport."
Now, I fortunately have black-white copies of my old passport's ID page and the visa in it as a PDF file on my laptop.
So my question is, will I be troubled upon leaving Paris with the Eurostar? I got in without problems so I'm hoping it won't be problematic leaving either. Even if I'm troubled, will my PDF copy help to the point that I can get through immigration? If extra money/cost is involved, I am helpless since I don't have any credit/debit card now. The new replacement debit card is probably waiting to be activated, in my house in the UK.
Will this be a big problem? I have my student ID if that helps to prove I'm a student.