Originally Posted by
Taenaeris
The in-game addon is only updated once a day, though you can update it more frequently when using the desktop app. And with the mass lookup button that they added to the group finder, using the web sites isn't actually all that bad.
About high pop servers, I played on both Thrall and Zul'jin in Legion - and while this was actually a problem prior to the Antorus release on Zul'jin, I've never really had any problems with runs not counting after Blizzard increased the size of their leaderboard. This is obviously a Blizzard API problem and not something the website / addon could do anything about.
And it can also be completely circumvented by inviting somebody from a low-pop realm into your group.