Red Devil
The Power of Connected
So the attendance bonus is chosen entirely at the will of the company.
You won't find any contract article on that that I know of.
You were also a seasonal, from the sounds of it.
So you were probably terminated and quietly rehired in the system, as happens every year with those that get kept after peak.
Also being a seasonal "at will" employee, you have basically no protections, or rights to the contract guarantees.
I know that's not the answer you want, but it's the hand you were dealt.
You get to choose to accept it, or try your luck elsewhere.
What they took away was MRA not attendance bonus.
Both of which are above and beyond the negotiated wage and completely at the company’s discretion.