This issue also exists in macOS Big Sur betas 7 and 8, and is causing crashes in live apps. We're working on new releases switching to NSURLSession, but there will be a significant number of users who may not receive the app update before the OS update.
Could you confirm if the bug will be fixed in macOS as well as iOS? I understand a time frame is not available but confirmation the issue is associated with both platforms would be great as this has significant potential to disrupt our customers and our businesses.