NOVA seasons 48/49 episode number problem
IMDb generally follows NOVA episode numbers. However IMDb always numbers episodes by broadcast date. Per this conversation:
both NOVA and IMDb seasons start with the new year.
At least as late as 2021/12/10 that was true for NOVA seasons 48 and 49. Season 48 was the 2021 season. Air dates for the first 5 broadcasts of 2022 were available from PBS and the episodes did indeed air on those dates (and IMDb has those correct air dates).
At some point of time, someone renumbered all of the season 48 episodes with air dates in September and later as season 49. The first 5 episodes broadcast in 2022 were renumbered to fit after the last episode of 2021. All subsequent episodes have followed sequentially.
This is the exact problem that was fixed in the conversation that I linked above (making IMDb seasons start in September when NOVA seasons start in January).
And while I'm at it, some contributor actually put a future episode (to air in July) in season 50 (which would normally start in 2023)! [Life is just full of surprises, isn't it? :-)]