I was looking up the Connie the Cow article on Wikipedia and read there was one triple-length episode. The rest of the episode list wasn't filled out on Wikipedia (only 18 episodes were listed at first), so I had to fill out the rest myself using my 2011 Connie the Cow Season 1 DVD and the rest of the episodes from Starz.
There's 3 seasons, 44 episodes and 130 segments in the show (actually there's 128 segments and 1 pilot episode as far as I counted). However, out of the 130 segments I counted, the triple-length episode wasn't listed anywhere, so I had to keep searching around the Internet researching a list of episodes until I got to TWC Central's website, where it listed "Connie and the Diamond" as an episode (it doesn't have a picture on the left, and the big text simply says "Connie the Cow"). However, that one wasn't listed on any episode lists, so I'm assuming "Connie and the Diamond" might be the one triple-length episode (or even possibly the series finale), but for some reason, Starz didn't list it, plus I can't tell if it ever aired on Noggin or if the episode itself even existed in the first place, since most other sites that list episodes for this show don't have it.
And "Hedgy's Spines/Mummy Tells a Story" bizarrely only had two 7-minute segments totaling that segment episode to 14 minutes instead of 22, and I don't know if or if not a third segment was aired along with those, so I can't tell if "Connie and the Diamond" is either the rumored triple-length episode or the third segment with "Hedgy's Spines/Mummy Tells a Story".
If anyone finds any info about the "Connie and the Diamond" episode, bring it up in the comment thread below.
UPDATE 1/5/19: Now we finally know that the episode exists and what the episode is about, thanks to someone who remembers seeing it on TV. Now if only someone happens to have the special taped off TV somehow...