Apple will close the Epic Games developer account on August 28, all its apps will stop working.
Added the official statement from Apple on the situation at the end of the article.
As reported by Epic, Apple is planning completely cancel the Epic Games developer account next August 28. The result of this action will be the removal of all your apps from the App Store and the apps already installed will stop working.
Consequences: a total shutdown
With the closure of the developer account Apple revokes all certificates necessary to run the apps. This means that, if this closure is fulfilled, all Epic apps, including of course Fortnite, even if they are already downloaded on the different devices, will stop working. Along with this withdrawal, Apple will prevent access to tools such as Unreal Engine that Epic offers third-party developers to create games. Epic’s response to this announcement has been a complaint to the Northern California court, requesting that this move be prevented by Apple.

Apple has advised of its intentions in a letter addressed to Epic Games in which they are invites you to continue complying with the rules of the App Store to avoid it.
After a more detailed analysis of the activity associated with your participation in the Apple Developer Program, we have identified several violations of the Apple Developer Program License Agreement. Therefore, your Apple Developer Program account will be terminated if the violations listed below are not remedied within 14 days. […]
If your membership is canceled, you will no longer be able to submit apps to the App Store and apps that are still available for distribution will be removed. You will also lose access to the following programs, technologies, and capabilities:

- All Apple software, SDK, API and development tools.
- Pre-release versions of iOS, iPad OS, macOS, tvOS, watchOS.
- Pre-release versions of beta tools like Reality Composer, Create ML, Apple Configurator, etc.
- Notary service for MacOS applications.
- App Store Connect platform and support (eg, account transition assistance, password reset, app name issues).
- TestFlight.
- Access to the provisioning portal for the generation of certificates and the generation of provisioning profiles.
- Ability to enable Apple services in the app (i.e. Apple Pay, CloudKit, PassKit, Music Kit, HomeKit, Push Notifications, Siri Shortcuts, Sign in with Apple, Core Extensions, FairPlay Streaming).
- Access to the keys issued by Apple to connect to services such as MusicKit, DeviceCheck, APN, CloudKit, Wallet, etc.
- Access to the signature certificates of the developer ID and the Kernel Extension.
- Technical support for developers.
- Participation in the Universal App Quick Start Program, including the right to use the Developer Transition Kit (which must be returned to Apple).
- Engineering efforts to improve the performance of Unreal Engine hardware and software on Mac and iOS hardware; optimize the Unreal Engine on the Mac for creative workflows, virtual sets, and your CI / Building systems; and adoption and support of ARKit features and future VR features on Unreal Engine by their XR team.
We hope that you will be able to rectify your violations of the Apple Program License Agreement and that you will continue to participate in the program.
Cutting access to the development tools offered by Epic for both iOS / iPadOS and macOS will have a major impact on apps and games that use the Unreal Engine. Due to the revocation of the notarial certificates Epic apps will throw an error when run on Mac (from Mojave), warning that it is an insecure app.

It is clear that Apple’s pulse is not shaking when it comes to enforcing the App Store rules and that last week’s move by Epic, defying the rules to denounce both Apple and Google after they withdrew the app of your stores, is going to have consequences.
This is the official statement that Apple has shared with SamaGame:

The App Store is designed to be a safe and trusted place for users and a great business opportunity for all developers. Epic has been one of the most successful developers on the App Store, growing into a multi-billion dollar business reaching millions of iOS customers around the world. We want to keep the company as part of the Apple Developer Program and its apps in the Store. The problem that Epic has created for itself is one that can be easily remedied if they submit an update to their app that reverts it to meet the guidelines they agreed to apply to all developers. We will not make an exception for Epic because we do not believe it is correct to put your business interests before the guidelines that protect our customers.