So I remembered an incident where someone had 3518 turns
Then I realized that the extra 18 is 0.5% of 3500 rounded up. +0.5% of max turns replenishing is what Holotrout gives. So I bought one from Armoury, and ate it.
This is the result:

This was something that I did deliberately, or at the very least, when I noticed it, I decided that it was useful. That was a long time ago though, and now I'm 50:50. It is inconsistent that they have that behaviour, and there's not really a benefit to it, because you could simply consume them once you've used some of the existing turns.

Fixed