PHP max execution time issues / Host Build interrupt

Hi,
I’ve got a strange issue that I hope you can help me with.
Archive building failed with a Host Build Interrupt / 500 Internal Server Error.
I then changed the max_execution_timeout of PHP from the default 30 seconds to either 3600s or 0 (unlimited), but I still get the Host Build Interrupt, and in its report it still tells me that “Allowed Runtine” is 31 (Isn’t this the 30 seconds of max_execution_time?), but in the line below it recohnized my max_execution_time change correctly. So why is the “Allowed Runtime” still so low? Or do I get something seriously wrong here?

In the screenshot at https://www.daniel-hertrich.photo/cloud/s/MHGLKhwgGfzdNi6 you can see that it recognized my config change to 0 (“unlimited”). When I changed it to 3600, the 3600 was mentioned there, too. Just the “31” always stays the same…

Thanks,
Daniel