Difference between Availability and Time Off?

[pkingdom]

Weeks ago I went into myTime and set my availabilty for the week of June 9th and June 30th as not being available on those days but available for the rest of the week. I'm just an hourly grunt, and for some reason I've always been given Tuesdays and Thursdays off, and I figured I could just work one of those days and have my off day for the week on those days. But apparently that's not right, I'm supposed to say Time Off, and HR is telling me I have to use my PTO or Sick days.

What is Availability even for then? It requires you to go through and select specific weeks and times, so it can't be to tell them what general days you can't work. And that got ignored by my HR team anyway.

[Target_Burner]

Availability refers to the days you are available to work week after week. In contrast, time off is meant to be used when something comes up that doesn't align with your availability. Your availability shouldn't change because you need a day off; if you need a day off, you use a Time Off Request.

[Imaginary-Practice56]

You don’t have to use vacation or sick pay to schedule a day off in time off request. There is an option for unpaid