it kinda is :) - 10 years in, we're just getting started!

It said S21 but was changed to S12 so you were right in your assumption.

There was also this one just a few weeks ago - just a coincidence, btw:

Launch HN: RescueTime (YC W08) – Redesigned for wellness, balance, remote work - https://news.ycombinator.com/item?id=28683597 - Sept 2021 (141 comments)