The hardfork 26 had a small bug that only affected backup witnesses, like me. Due to that bug I couldn't produce blocks for a long time, but hardfork 27 came very fast and fixed it.
Until earlier today my witness was, mistakenly, seen as "inactive" because the last block produced was on the Hardfork 26 and over 1 week ago. Now everything is up and running normally.
By publishing this block the blockchain can see that I am active and my node is working and also I am on the correct version of the software.
Hive an amazing piece of software and the consensus we have allows for fast changes and corrections. Color me impressed.