CoreBluetooth characteristics reading differs on iPhone 12

I've encountered a strange issue reading characteristics from a BLE device using CoreBluetooth ONLY ON iPHONE 12 AND iPHONE 12 PRO.

The problem is that the BLE device receives a read characteristic request for an errored characteristic id.

The BLE Device is using blue kitchen btstack (https://github.com/bluekitchen/btstack). We also filed a bug report on their side here

Say i ask for a characteristic discovered with CBUUID "F97A6DA4-B3AA-44B0-8DE7-40D238BE5E02", the device receives a request for a "F97A6DA4-B3AA-44B0-8DE7-40D238BE5E09" id.

The exact same swift code is working perfectly on MacOS, reading the right characteristic on the device. I is also perfectly fine, tested on various iOS versions on iPhone 8, SE (1st gen), 11, 13, 15. The only devices affected are the 12 & 12 Pro.

I also tried using popular apps like light blue, or nRF Connect for iOS, and the iOS app has the same behavior on iPhone 12 & 12 Pro (that is wrong), but is ok on other iPhone devices.

Has anyone encountered such a strange behavior and have any insight on how to solve that ?