thanks for your impressive dd-are you on vacation?
your post provides some perpsective on various drilling platforms,including f400-though, i think zn had a different variation of a '400' drill, since drill zn was using is rated to 23000 feet, as you noted earlier. https://dafora.ro/drilling-fleet/
but in that one article re zn's well i presume that is a pic of the rig used to drill zn's well