ArcGIS Pro generates Vector Tiles up to maxLoD 15, even when requested maxzoom is say 19. Still after publishing a vector tile package which has vector tile bundles available only till LoD15 to ArcGIS Online the tiles for example for Level 17 are available (although not present in the original VTPK!). From what I can see they are derived/resampled from 'parent' tile:
Above can be seen in the http header for requests for PBFs such derived tiles, in this case it was Level 17. Then the highlighted bit is what seems to be the parent tile. Is there any code snippet available on how is this resampling/deriving done please? Is this done on the fly per each request or is ArcGIS Online deriving/resampling those during the publishing of the service please?