When exporting a Tumult Hype document, a number is added to the end of the document's JS file:
<div id="index_hype_container" style="margin:auto;position:relative;width:600px;height:400px;overflow:hidden;" aria-live="polite">
(The number 4036, for this example, which is almost the last character in the last line). This is a query string which browsers should understand: it means 'don't cache this JS file'.
If that's in place it should be reloading each time someone visits. If that's not the case can you share a document? A more forceful way to reload is to change the actual name of your document when you export.