We have a requirement to share Pega URLs with external systems to access cases in review mode. We have been using URLs containing custom activities (ex: ?pyActivity=ReviewCaseDetails&Key=<CaseID>) but with the URL encryption added, plain URLs with pyActivity parameters will be rejected. So we are considering to encrypt the URLs using OOTB mechanism before sharing with external systems as shown below.

var encryptedURL = pzEncryptURLActionString(tools, "Global", "pyActivity=ReviewCaseDetails&Key=<CaseID>");

Here we have a question about the expiry of these URLs with Global scope. Will these encrypted URLs with Global scope work forever or is there any expiry ? Our use case is to support the URLs at least for 1-2 years. 

Any insights would be helpful. Thank you in advance.