New Crashes with iOS 13.5.1

Code that has been consistently stable for a long time now has begun crashing for unknown reasons in my productions apps since the release of 13.5.1

Example 1: Handling a SKPaymentTransaction in the failed case, it is supposed to always be guaranteed an error so my code always force unwrapped it using !. Since first releasing the app 3 years ago until 13.5.1 this has never been an issue before but now the number of crashes regarding this are suddenly increasing, with the last 24 hours seeing 40-50 crashes for this and all my users experiencing this crash are on iOS 13.5.1 or greater

Example 2: Fatal error: Index out of range: file /Library/Caches/com.apple.xbs/Sources/swiftlang/swiftlang-1103.2.25.8/swift/stdlib/public/core/ContiguousArrayBuffer.swift, line 444
At first glance, this seems pretty obvious. Index array out of bounds, I must have done something silly. Except, wait, my code has been out and stably released for some time now but with the rising adoption of 13.5.1 I have multiple cases of this occurring through my app where it has never been affected before.

Both of these scenarios are rather easy to add aguard to resolve, but I would rather understand the core change that is effecting these to know fundamentally what changed with 13.5.1 that is affecting my app out of nowhere.

If anyone has any ideas, I'd greatly appreciate it
mmdok, I'm experiencing the exact same situation with an app that has been stable for years and now gets the EXACT same ContiguousArrayBuffer error. I am not using the StoreKit, so this appears to be a change in the ContiguousArrayBuffer class.

This has me stumped for how to solve.
New Crashes with iOS 13.5.1
 
 
Q