If the signature expires, you can find the original signer to renew it. If you can't get in touch, you can find a new signer to sign.

Enter the developer center, click "iOS Enterprise Signature" in the left navigation bar to upload ipa file and sign it.

You can't continue to use expired signatures. When the signature expires or is cancelled, the following information will be displayed, which can only be used if it is renewed or re-signed.

Benefits of applying signatures:

1, application upgrade. If you want to upgrade the version of the application, you must sign it with the same certificate, because the system will only allow you to install and upgrade this application if you sign it with the same certificate. If the user signs with a different certificate, the system will ask the application to change its name, which is equivalent to installing a new application.

2. If different applications want to share data or code, they should run in the same process and sign with the same certificate. Sign multiple applications with the same certificate, and use the permission check based on signature to enjoy the code and data between applications in a safe way.