I upgraded to 2.30 with no problems at all. However, the upgrade to 2.31 is a mess. (1) After install, initial page is white page. By reloading common.php file from 2.30 pages are displayed again. (2) Calendar (extcal) no longer displays the month or submit entry in block. (3) Admin page for modules "system" and "extcal" titles are missing. Database is updated with blanks in those fields. (3) Any attempt to edit a calendar entry blanks out the entire record in the database.

I have not attempted any other database entries of any other modules, but I suspect that they will all blank out the records.