That essentially means the launch date is subject to move, based on un-confirmed/un-reliable sources, etc - GO for Launch means there is publicly posted informa

That essentially means the launch date is subject to move, based on un-confirmed/un-reliable sources, etc - GO for Launch means there is publicly posted information from the launch service provider or some other first party source that confirms the date. Most launches end up being No-GO until the week or so before.