Maintenance downtime NOT matching the sched

I understand maintenance on the servers is occasionally necessary. Six hours a week seems excessive (especially when other "free" internet services like eBay get by with minutes of downtime per YEAR, and arguably have a greater financial commitment to correctness), but that's a separate issue. We are all paying for this service, but Blizzard needs their occasional downtime to keep it running, fine.

I'm writing to complain about the consistent and repeated INACCURACY of the maintenance schedule. Today's downtime was scheduled for 5AM PST - 11AM PST. In actuality, servers did not go down until 10AM PST (ie one hour before maintenance was scheduled to be DONE), and the maintenance period has been extended twice, currently targeted for 3PM PST. Consequently, the original schedule of 6 hours has slipped to 10 hours, possibly more.

As a paying customer I find this unacceptable. Players and guilds schedule activities and events around maintenance times, expecting the company to honor their uptime commitments. Please do a better job of minimizing downtimes and sticking to posted schedules - it matters.