Hello [mention removed],
Sorry for the delay in response. I was able to reproduce the issue in UE 5.4 as described. However, after testing the same setup in both UE 5.5 and 5.6, I can confirm that the issue no longer occurs. The array and all FInstancedStruct entries behave as expected even after populating them with Blueprint-defined structs.
That said, migrating a project from UE 5.4 to 5.5 won’t resolve corrupted class default data already saved in Blueprints or levels. You’ll need to replace or reconfigure affected actors to clear out the broken data. Once that’s done, everything should function normally.
It’s also worth noting that as of UE 5.5, StructUtils has been marked as production-ready and is now part of the main engine module, per the official release notes.
Please let me know if this information helps.
Best,
Francisco