Export Books is not working (again)

My export (All books, Tab-Delimited) had been sitting on 0 books processed for more than hour.

This is my third attempt to export my complete library in as many days.
Wednesday:
- Test run, exporting just Currently Reading, works in milliseconds, get a notification, downloaded the export, all good.
- Started the full export. Opened the export page again in 5 minutes, it told me it has a working export going so I walked away. Never got an error, no notification and when I looked at the export screen again the next morning there was no indication that I have a running export anywhere.

Thursday:
Started the full export and just let it run after a refresh to see that the system thinks that there is a pending export. No news.

Friday
No notification, no indication on the page that there is anything running. Started the export some time earlier this morning and left the page open: "0 books processed" stayed like that every time I looked. Just refreshed the page:
"You have 1 export waiting or in progress. Please wait for these to complete before starting a new export. 1 waiting in queue."

So two issues really:
- What happened with my exports from Wednesday and Thursday?
- And just how long does an export take these days (for today's)...

PS: I have 2,368 books in this account which I don't really consider a big library...

Update: an export just completed.

Still not sure what happened with the exports from yesterday and the day before that (or is this one of the older ones?)