Okay, I'm sorry, I was completely wrong. (mostly wrong)

It seems that SOME entries acquired the timestamp of the time of import, but not all. In fact, probably not most.

Terribly sorry for the bum-steer, but there are definitely a few entries are incorrect. Those entries don't appear to have any noticeable corruption when viewed in Thunderbird (i.e. no missing timestamps, garbled display, etc).

I also can't be sure if any other recent emails have had incorrect timestamps applied to them during import.

Hi sgunhouse,
The months, dates & times are all correct, it's just the year, which is all 2015.

I believe they did import in the correct order, but I wanted to sort in the opposite date direction (newest at bottom), so I clicked the 'Sent' column header and that's when I noticed emails from a long time ago had re-appeared interspersed with current emails. (But it did take me a minute to work out that it wasn't ghosts from the past )

Hello,
I just installed Opera Mail (v1.0 build 1040, Win8.1) and imported my mail from Thunderbird.
Great feature(!) but all the mail is marked as 2015, including emails that date back to 2008.

I'm really wanting to ditch buggy Thunderbird, so hopefully there'll be a quick fix for this.

All the best,
Dax.