This is the plan:
- Close the forums.
- Backup the database.
- Upload the new vBulletin 4.1.10 files.
- Upgrade the forums.
- Fix the most urgent problems.
- Open the forums.
- Fix the less important problems.
Preferably, I should upgrade when nobody is watching, but I must also have time for that, so I'll start next Friday 23:00 GMT+1 (my local time). I expect to be a little bit faster than last time. Probably, I'll need one hour.