Large userbase is troublesome for Telegram
According to Pavel Durov, one of recent updates for the Telegram app had to be delivered as soon as possible due to a breaking change: the messenger is moving to int64 data format. Let's find out what that is and how does it impact the messenger.
Each user, channel, and chat get a unique identifier assigned to it. Since the launch of the service, this identifier is being stored in a 32 bits sized memory cell. This means the maximum user count this identifier can express equals to about two billion entities.
Telegram keeps approaching this limit, so the team urgently updated all their apps to support 64-bit sized numbers (max value of which is about nine quintillions), since it's impossible to solve the problem without an app update.
Telegram is smart about using their current numeric space, they assign identifiers in according number ranges based on user's region and registration time, but the team is running out of these ranges. Recent userbase growth caused by Facebook services unreachability (70M new users) made this problem even worse.
According to a Russian channel ะกะะะ!, the messenger team started using their last available range of the old type identifiers for 50M future users which should last for about two months.
To avoid possible problems, you need to update your app to the recent version as soon as possible. It's unknown how the messenger team is going to work around this problem, but recently Telegram's documentation was updated to introduce a mechanism for forced updates, which was likely designed for the smooth transition to the identifiers of the new size.
Source: tginfoen