NOOOoooo...
Sigh. A "last minute" change, this morning, to actually put in the extra coal veins that I was planning on doing but never got around to.
Except, as I'm plugging the lava leaks, I discover that ores are not considered "supporting stone" by reasonable realism ... Most of the extra holes are easy enough to plug, but I got over to the stronghold library, one of your quest points basically ... and it's completely gutted by fire from a lava leak where coal didn't support stone and the roof collapsed.
Ayye.
Fixable? Yes. Not in the remaining 25 minutes. To ship something now, I have to ship my debugging map.