Receiving a Director Penalty Notice puts your client on a strict 21-day clock...

https://www.ready-bookmarks.win/director-penalty-notices-wait-for-no-one-the-21-day-clock-starts-the-moment

Receiving a Director Penalty Notice puts your client on a strict 21-day clock starting from the issue date. The consequences depend heavily on whether it’s a lockdown or non-lockdown notice