Strange EXC_BAD_ACCESS on iOS when calling a delegate

Development Getting Started & Setup
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1

Hi there Answerhubbies,

we discovered a strange bug when we updated to 4.25 (may already been also in 4.24).
We implemented an Object that serves as and DeviceManager to connect to Bluetooth Devices via a C++ Plugin.
Works fine so far, but on iOS we discovered strange issues sometimes, when the Plugin in calling Delegate Functions.

First there was an EXC_BAD_ACCESS Error during a contains call on a TMap which held the according delegate function. So we got rid of the TMaps but still unfortunately there is an error thrown when accessing the delegate itself.

We pinpoint it down to this function callstack:

OnReadSuccessSingleDelegate.ExecuteIfBound(byteData); //Delegate is called)

This will call a function in the ScriptDelegate.h

inline bool IsBound() const
{
	return IsBound_Internal<UObject>();
}

Which leads to:

template <class UObjectTemplate>
inline bool IsBound_Internal() const
{
	if (FunctionName != NAME_None)
	{
		if (UObject* ObjectPtr = Object.Get())
		{
			return ((UObjectTemplate*)ObjectPtr)->FindFunction(FunctionName) != nullptr;
		}
	}

	return false;
}

And finally escalates here:

FORCEINLINE bool operator!=(EName Ename) const
{
	return (ComparisonIndex != Ename) | (GetNumber() != 0);  //Thread 13: EXC_BAD_ACCESS (code=1, address=0x131680ea8)

}

Anyone stumbled upon a similar issue? The Delegate is created fine on android (no issue there).
Also it seems that it is happening more often during a map change. Any hints on how to investigate this issue further is highly appreciated!

Greetings b.ReX