Update coordinate system of hosted feature layer?

[mingster]

Is it possible to update the coordinate system of a hosted feature layer in ArcGIS Pro without overwriting it? I published a hosted feature layer (DWMS4Outfall) and it looks like I forgot to set the projected coordinate system to NAD 1983 StatePlane California VI FIPS 0406 Feet. Other layers I published show both PCS and GCS under Spatial Reference (e.g., RWStation). If I need to republish/overwrite, how can it be done without losing the attachments?

Thanks for the help. 

 

[wtfineberg]

@SierraNevada, I cannot speak to the LSL Solution specifically, but I was able to modify the Spatial Reference (SR) of an AGOL hosted feature layer (HFL) following the guidance from @BrittanyBurson. Setting the SR on the map itself is what seems to impact the SR used by the HFL. This does seem to affect the service as a whole, even for end users that do not use Pro. Although what you may be experiencing might be related to re-projection on-the-fly within web maps, which I believe is standard behavior for AGOL web maps?

Here are the steps I followed to overwrite the SR of a HFL without publishing a new item:

1. Add new Map to an ArcGIS Pro Project, re-name it according to the HFL. Remove the default basemaps.
2. Open the properties of this new map.
   1. Enable "Allow assignment of unique numeric IDs..." in General.
   2. Set the desired SR in the Coordinate Systems section.
3. Add the desired data to this map, already projected to my desired SR, which is the same as what I just set this map to use.
4. In the properties of the added dataset(s), set the desired Layer ID to match the existing HFL structure.
5. In the Share tab, click the dropdown under Web Layer, then select Overwrite Web Layer. Select my desired Web Layer to overwrite.
6. Compare and Analyze, then Publish once everything looks good. Once complete, navigate to the REST page from the AGOL Item Overview page and confirm the SR was modified.