Angry

I am really upset with my supervisor and also glad that I am planning on moving to another city soon. I have worked part time at this job for 2 years. I only get one 8 hour shoft and then fill in for the full time people. I was a little upset when they hired another part time person but realize that they probably needed to because there are some shifts I can't cover.
Then last night I came into work and there was a note from my boss that there was a new person starting and to tell her my supervisor would be there at 11:30 to train her. When the new person gets there I start talking to her. Curious why they hired yet another part time person. They don't need someone to fill in enough to have 3 part time people. It turns out one of the full time people is going to part time and this person was hired to work 24 hours a week that the full time person used to work. My supervisor never told me that this person was going to part time and to see if I wanted any of her hours. I can't believe she wouldn't check with me before hiring someone else. She knows that I work any extra shift I can and that I need more hours. The least she could have done was have the courtesy to see if I wanted the newly available hours.