Easiest way to find a pdf is to let the reader app find it for you. Open the pdf viewer and it will search your phone for all compatible files.
Tried that but this particular file doesn’t come up. I don’t know if that is because it may be saved to the phone or whether it is because Android didn’t actually save it (when I tried to open it using adobe reader, it said it could not open the file so perhaps it just deleted it from the preview cache?).
I’ve found the folders Downloads and Downloaded, but its not in either. I think I may have answered my own question above and it had just cached a preview of the pdf.
So basically there is no way to manage/organise files other than by using an app like astro?
Thanks all for the help.