OK I lay this one totally at the feet of the outgoing executive.
The event calendar (left side) displays all upcoming events for next 31 days.
@ 9PM Mountain time (this server is in Texas) the AGM event, on the calendar was no longer something coming up, but something in the past (well, at least according to the clock on the server).
So, the logic in the event calendar, looked ahead and saw no more entries for next 31 days... And nicely tells us that fact. When it does it improperly closed some HTML table entries that it does need when there are events to display.
The result, a very messy Site.
So it is the outgoing Executives fault, if they did not resign, and kept that darn AGM going, the site would have stayed all pretty.
Irene saw the 'no events in next 31 days' message, and on a hunch turned off the module, which fixed the page.
I have since gone into the code, and corrected it. Funny thing is the 3rd party software has 3 other similar modules that do it correctly, but the format we picked had a bug.