Upgrade worked fine. However, step 2 counted up to more than 380000 (last number I saw before making a cup of tea) quite slowly which I was not expecting. Security updates have historically been quick, just amending a few source files, so I didn't notify my users of the downtime in advance. I think it took in the region of 40 minutes - I didn't note the time it started. I assume this was adjusting something for messages, or attachments, or similar, where the size/age of forum is relevant?
