The tweet claims that if users were to update to iOS 14, they might see a message that asks them to temporarily remove apps ahead of the update, and doing so would uninstall Fortnite and players will not be able to get it back. This is because in case you haven’t heard, Apple has removed Fortnite from the App Store, and users will not be able to redownload it again once it’s been uninstalled.
Instead, the tweet is suggesting that users should manually uninstall or offload unused apps before installing the update. Note that this seems to only apply to iOS devices that do not have enough storage for the update to begin with, which is why iOS might prompt them to uninstall apps before updating.
Fortnite iOS players updating to iOS 14 may lose access to Fortnite. If the message “Temporarily Remove Apps to Install the Software Update?” is accepted, it may result in Fortnite being deleted. Fortnite cannot later be reinstalled due to Apple preventing users from doing so.
— Fortnite Status (@FortniteStatus) September 23, 2020
Personally I did not encounter this issue during the update to iOS 14, but it’s worth taking note of anyway. In the meantime, we should also point out that even if you have Fortnite installed, the removal of the game also means that you will no longer be able to receive future updates and you will also no longer be able to play the game with non-iOS gamers.