Annotator, supper gatherer and slammer of thunderous high fives
A big ball of Wibbly-Wobbly, Timey-Wimey _stuff_
Cheers, Simon. What seems to be happening is that it's basing the page calculations on the assumption that there are 10 posts per page, when in reality there are currently 15 posts per page. So, on page 1 of the megathread, the permalinks for posts 1–10 get mapped correctly, while those for posts 11–15 get mapped incorrectly to page 2. Then on page 2, posts 1–5 get mapped correctly, but 6–15 get mapped to page 3. From the top of page 3 onwards all of the mappings are off.