Hi again. Thank you for your reply.
Q: When I hired in, I was never informed that I have to be available 365 days per year. Does that provide me with an argument if necessary?
A: No, that doesn't help, I'm sorry to say. Only an employment contract
that specifies the days that you work would be helpful. Without a contract, the terms of employment are subject to change at any time.
Q: If an employer informs me on Thursday or Friday that I have to work the weekend after putting in my 40 hours, but have already made personal plans, can I refuse the work without being fired?
A: Unfortunately, the answer is no. You can be fired for any reason, so long as the reason is not based upon illegal discrimination
, such as your race, religion, gender, etc. You can be fired for refusing to work the weekend even if you've only be give 1 minute notice. The right of the employer to terminate you like that corresponds to your right to quit just as quickly. For example, your employer could tell you that you must work the weekend, and you could immediately quit. With few exceptions which do not appear to apply here (like illegal discrimination), either the employer or employee can change the terms of employment at any time and for any reason, including whether you will work and remain employed.
I hope that helps. Let me know if you need clarification.