If you were a Twitterrific or Tweetbot user, you should download the latest versions of those apps from the App Store and launch them. Here’s why: https://daringfireball.net/2023/03/tweetbot_and_twitterrific_face_the_cliff
Tweetbot and Twitterrific Face the Cliff

There is something noble about two longtime rivals — competitors, yes, but with nothing but deep respect and camaraderie for each other — facing this terrible cliff together, with dignity and grace, considering their users first, as ever.

Daring Fireball

@siracusa I cannot stress enough how important it is to do this step, even if you've been super close to the end of a subscription.

In my case there's only 3 days between the end of my Tweetbot subscription and the start of the Ivory one. Perfect I thought, that will just round to zero, right? But @tapbots would still need to refund me 21 days because it counts from the Bird cut off date.

Nothing but noble that this is opt-in. But man, subscriptions are high risk for devs.

@console @siracusa @tapbots Re: subscriptions as high-risk, maybe I’m missing something but isn’t this particular type of scenario extremely rare or perhaps even totally unprecedented? I can’t think of any other case that’s even remotely close to this situation, meaning a platform owner cutting off its partners no upfront warning or transition period.
@Richard2001 @console @siracusa @tapbots This is what I came to say. You can find single-person shops that are facing bankruptcy that still would have provided a proper sunset period. The idea of --anyone-- the scale of twitter just wordlessly cutting off an API entirely is wild. im guessing we’d have to go to the dotcom bubble to find something similar.