Hi!
I'll do a presentation next week, in which I intend to demonstrate that I can add a Wikidata value online, which then is available immediately for my application - as well as for the whole rest of the world. (In Library Land, that's a real blast, because business processes related to authority data often take weeks or month ...)
I think we'll always have some way to run un-cached query. The question is only how easy would it be - i.e. would you need to add parameter, click a checkbox, etc.