An episode that ends around 10:23 pm tends to be followed by another one, which is roughly how a reasonable night becomes a short one. Seeing the exact time remaining, ticking down rather than sitting still, makes that decision a conscious one instead of something that just happens.
When the clock reaches 10:23 pm, the count does not sit at zero. It rolls straight over and begins again towards the same time tomorrow, on its own, without a refresh or a reset. That makes this a page worth keeping in a bookmarks bar rather than one you look at once and forget.
Between the last Sunday in March and the last Sunday in October the country runs on BST rather than GMT, which is why timetables and confirmations sometimes carry the label as well as the number. This page counts down to 10:23 pm using whatever your device is currently set to, so the switch is handled for you.
Common questions
Is it affected by the clocks changing?
Only in the sense that your device is. When the change between GMT and BST happens at the end of March and October, the device adjusts and the countdown follows it without anything to do here.
What is 22:23 in the 12-hour clock?
That is 10:23 pm, or twenty-three minutes past ten at night if you are saying it aloud. From 13:00 onwards, subtracting twelve gives the pm figure — the same moment written three different ways.
Does the number update by itself?
Yes. It recalculates every second from your device's clock, so there is nothing to refresh or restart. Whatever is on screen is the current gap to the target time, not a figure worked out when the page first loaded.
What happens if 10:23 pm has already gone for today?
The count simply carries on towards the next occurrence, which is tomorrow. That rollover happens on its own — the page does not need reloading and there is nothing to reset by hand.