What should I enter for the last port of embarkation on my retirement visa application, and how can I successfully upload my bank statements?

I submitted 3 separate, they responded asking for missing, i uploaded 2nd, they asked again, i uploaded 3rd month

I combined 3 bank statements into one document.

They replied by sending me separate blank attachments.

If this is for the visa application itself I would put the departure city from your country that you're leaving from seeing as you have to be in your country when you apply for the Visa that's where you'd be leaving from once you get it.

If this is just for that tdac arrival card online program, they don't care, put whatever you want.

As far as the conundrum that you can only upload one file, use a search engine and search for file combiner online so that you can combine all the jpegs into one file and upload it in the required spot.