several Stream BarChart errors that are not present in the documentation

[finete]

I have been using the WebAPI for some time and I have received several error messages that I didn't see in the documentation.
These are Error messages that you sometimes receive from the Stream BarChart GET functions:

ERROR - FAILED, EX_INVALID_SYMBOL
ERROR - No data available.
ERROR - RESET
ERROR - DATAFEED_NOT_CONNECTED
ERROR - FAILED, EX_NOT_ENTITLED
ERROR - FAILED, EX_NO_DATA_AVAILABLE
ERROR - Unable to retrieve exchange utc offset minutes - RESET
ERROR - The operation has timed out.

It would be helpful if they (and their meaning) were documented. Are there any more error messages?

I saw in the doc that the way to handle ERROR message from a stream is to

the HTTP client must terminate the HTTP Stream ... the client application may add a delay before re-requesting the HTTP Stream

Is this the case for all error messages?
For example doesn't ERROR - FAILED, EX_INVALID_SYMBOL supposed to be a 404 Symbol not found instead of a 200 status code?

Note that the status code of the GET request is 200 for all of them, meaning they are the text content of a successful GET request.