To be clear:

The Live button (js/app.js:486-493) ticks every second (setInterval(liveTick 1000))

During the eclipse window (16:00–20:00 UT on 12 Aug 2026) it computes the current UTC time sets the slider and calls updateLive() which interpolates the umbra position between the precomputed path crossings (positionAt app.js:382) and moves the umbra + penumbra circles on the map (app.js:419-421) now added a rec button too allows to save gif files with the duration max of 2m every.

So the circles time readout and countdown all update live every second.

Before 16:00 UT it shows a countdown after 20:00 UT it shows "Eclipse over"