I am making a Tick History (v2 - REST API) request for a "Stored and Scheduled" Request (TRTH API Guide Chapter 10). In the data payload for the example request in Step 4 there is a TimeZone specified. What is the allowed list of timezones for this field? I have tried others, e.g. UTC (acronym and full name) and GMT plus a few others and they are rejected. It looks like the default is GMT, and is echoed as "GMT Standard". And, why is it necessary to specify an ExtractionDateTime for an immediate request, when using a stored instrument list and stored template, where the template has the time range for the tick history query? I omitted both parameters from the request and it seems to work (didn't return any errors).