Schedule settings change on edit

A user reported this behavior, which confirms my initial suspicion.

1) If my backup time is set to 11:00 pm, when I click on the "Settings" link, the "Start time" "Hours" shows "6" instead of the expected "23".

If I put in "23" for "Hours" and click the "Update" button, the "Manage Backups" page does indicate that the next backup will be at 11:00 pm, as expected.

2) I can't use a value of "0" in the "Start time" "Hours" field. A red box appears stating that "Hours must be between 1 and 23". So I can't schedule a backup for the midnight hour?

3) Feedback: after upgrading to v2.6, the scheduled time of my two backup sets (one daily, one weekly), and the day of week for the weekly, were changed to the time, and day of week, at which the plugin was updated. This was easy enough to reset, but unexpected.