This afternoon, I had to install some (routine) updates, which required a reboot of the home computer I use to host this site. Therefore, this site would have been unavailable from about 12h45 to 13h00 using IPv4 addresses.
Further, due to some non-specific problem, my IPv6, Teredo-address was not up-to-date, until roughly 13h15 this afternoon. So IPv6 access would not have worked, since an earlier time this morning. And that exact starting point is not known to me.
I apologize for any inconvenience.