There is the section under a story's title that shows how long ago was the last update of that story. It never shows "11 months ago". It goes from "10 months ago" straight to "a year ago".
Yeah I suspect that's just due to how the site is set up to round the time difference from the timestamps. By the time it's 11 months you may as well call it a year anyway
The human-readable timestamps are created by third-party plugins. One of them is used for the timestamps that are updated while the page is open. The version we use rounds up to a year at 320 days, so at about 10.5 months. The other one creates non-changing timestamps. Those switch from 11 months to 1 year after about 365 days or so. If you load a page with an updated timestamp, you might also notice that the timestamp switches from 11 months to 1 year as the rounding one changes the precalculated (fixed) one. Yes. I think the plugin creators did that by design. (Though there is also a version that rounds up at 345 days.) The value "a few seconds ago" should change to "a minute ago" at 45 seconds. At 90 seconds, it should change to "2 minutes ago".
I've noticed sometimes that when a page loads the first time it might read as "17 seconds ago" for example and then rapidly switch to reading "a few seconds ago" So that would be the plugin at work, right?
Yes. The "17 seconds ago" is calculated by the server. The "a few seconds ago" is calculated by the user's browser.