Here’s an update:
So I got back to the head bolts, and checked torque.
On most of the bolts, I had to torque up to 1/3 or even 1/2 turn till I got to the target torque of 50Nm.
At this point I’m waiting a few hours (heck, even days) to check torque again, hoping they are done stretching..
Let’s wait and see!