What values can timeZone parameter take in JET timeseries plugin?

When retrieving timeseries using JET timeseries plugin, what values can one pass to timeZone parameter? The example in Eikon Web UI app uses "timeZone":"Instrument", which returns timestamps according to the time zone corresponding to the RIC. I figured out that if I don't provide timeZone parameter in the request, the timestamps are returned according to UTC. How can I get the timestamps in the time zone of the user (or the machine Eikon is running on)? I tried "User" and "Local" in every possible case: all upper case, all lower case, proper case. None of those worked. Timestamps were returned according to the time zone corresponding to the RIC.
In RHistory function in Eikon Excel I can also provide that I want timestamps in the time zone of a city, e.g. 'NYC' or 'LON'. Does JET timeseries plugin have the capability to return timestamps in a specific time zone?