OData V4 TripPin `PATCH` error: "Currently only EntitySets can be updated."

[boghyon]

1. Open https://output.jsbin.com/zimijuq
2. Open browser's devtool (F12 on Windows)
3. Select a new date range from the UI
4. Observe the error response in the network tab or in the console.

The server reports that the entity cannot be updated because the method PATCH is not yet supported:

The server responded with a status of 501 (Not Implemented).
Failed to update path /People('russellwhyte')/Trips(0)/StartsAt - Error: Currently only EntitySets can be updated.
Failed to update path /People('russellwhyte')/Trips(0)/EndsAt - Error: Currently only EntitySets can be updated.

Does the service really not support PATCH on a single entity? Or is the client missing something?

[boghyon]

Any update?