DataSet does not refresh from DataFlow (both with incremental refresh) from Storage Blob

So, we ended up using a Stream Analytics Job, that executes on a Gen2 Data Lake Blob.
This all works fine for some amount of days. The PowerBI report updates accordingly.  
Then, the data is updated in a FIFO-manner as observed. Previous data is no longer available to the report and later data is available. Where is this limitation set? Or is this a default limitation?
Also we get this error message:
" Warning: Blob scan operation scanned a large number ({#>485}) of older blobs. Please consider using the date/time path pattern to reduce the number of blobs that have to be listed."

The blob pattens is YYYY/MM/DDTHH/mm/ss, so the consideration is already matched.

Any idea on how to show more data than these ~215.000 records with Stream Analytics job on a PowerBI report? We are stuck.