Games get the abandoned tag if the dev doesn't post anything on their official pages (Patreon, SubscribeStar, etc...) for 3 months. The abandoned tag is also applied if there hasn't been an update in 18 months. The "on hold" tag is applied if the dev says the game is on hold.
The abandoned tag needs to be split into 2 different tags because not all so called abandoned games are abandoned equally.
One tag for "Confirmed Abandoned"
One tag for "Suspected Abandoned"
The reason why this abandoned tag was applied is the dev has gone 3 months without updating Patreon.
Maybe they are just really hard working on the game, and forgot to update it. It's possible, or maybe they had some real life drama they will get back to working on it soon.
October 28th is last contact from dev on Patreon, and they made 0 hint at it is abandoned.
At this point we can definitely suspect that Above The Clouds is abandoned. However, we can not confirm it.
Confirmed Abandon =
Dev comes out and says "I'm done" in their own words.
Patreon & Subscribe Star and other payment methods are closed down for the project
12 months have passed since the developer has said anything on Patreon or other payment methods.
Any or all of these 3 things will confirm abandonment.
Suspected Abandon =
3 months have passed since developer has said anything on Patreon etc
The dev has missed 2 or more self imposed release dates consecutively
They say, "I'm releasing March 1st" They don't... They put out another notice, "No no no I meant March 14th there has been some delays" March 14th comes and goes no release? That's abandoned!
12+ Months no release
Suspected Abandoned tag could also be called a "Milker" tag