@touhidur This is a very old post, and a lot has changed since then (as outlined here, here and here). These included reliability improvements made to the process that runs and evaluates your submissions.
Having said that, what you said is also true. In case your browser loses the WebSocket connection to the server and takes very long to fallback to AJAX long-polling to get real-time updates, the page may not show the latest data. And in that case, you will have to reload the webpage.