The Default Value for a Timespan variable resets to 00:00:00.000 whenever its Blueprint is compiled.
1. Launch: UE4Editor.exe (any project)
2. Create a new Actor Blueprint
3. Create a new variable of type Timespan
5. Enter a Default Value of anything other than 00:00:00.000
The Default Value reverts to 00:00:00.000 whenever the BP is compiled.
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