After this was merged graphprotocol#5160 substreams fatal errors can write SubgraphError{ block_ptr: None }. This introduces a bug that shows in Status API as those records can surface as fatalError.block = null violating the schema of type Block { hash: Bytes! number: BigInt! }

A later commit graphprotocol#5971 makes it much easier to trigger this when doing a status API that returns all subgraphs (empty [] array for deployment ID) as failed substreams linger on in the indexing status set as paused instead of being unassigned.