My aunt has a step 1a hearing at the hospital where she works what the that mean

It means she is being brought up on charges by the Agency. This is the first step in the disciplinary process. Its usually a meeting with your supervisor or manager. That is unless she had already had step 1,2 and 3 with the supervisor. That is more serious and can lead to termination or just a lost of pay.

Ask your rep

I am not really sure, you can call DC37 , maybe someone there could answer your question.