I upgrade GLA-DXB J to F recently. It was an email offer.

However, I did not get a confirmation email. I have checked the App and asked for a new ticket/itinerary to be emailed and the upgrade has been applied.

I need an invoice/receipt for the additional payment. Any idea how to get that?

On another note, what is the F part of the lounge like in Glasgow? If I want to use it do I have to pay the full F lounge fee or can I just pay an "upgrade" fee to upgrade my lounge access from J to F.

Last question, will I get the F dining experience with my upgrade ticket or is it a J meal?