Arranging, rearranging and unarranging.

One of my colleagues called in sick yesterday and will be out for the rest of the week, so I agreed to take over his some of his classes yesterday and today. I arranged it with Bosswoman, and then went off to teach. After finishing my class, I went downstairs to the office and noticed that the schedule had been rearranged again. I asked BW why she had changed her mind and she said that she hadn't changed anything that we had arranged, so I asked Bossman. He said that nothing had been done to cover the classes, so he took it upon himself to find teachers to do it. I told him that BW and I had already arranged it and made the changes to the schedule, before he rearranged it (not even noticing that the changed had been made.....it's hard not to, as we use a colour coded schedule). He then unarranged (yes, I know that's not a word) his rearranging.