Employment rights and mental health

[Snoopy111]

I’m looking for some advice for my daughter. She has a part time job that she started in April. She has completed her probationary period and has just returned to work after being signed off for a month due to mental health. Now she’s returned to work her employer has said they want to move her on to a zero hours contract. They have presented this as a supportive move to give them flexibility to vary their working hours depending on how they are feeling. I’m concerned this is discrimination and will mean they if they are signed off again at any point the employer won’t have to pay their sick pay.
can anyone offer any advice about my daughter’s rights please?

It's a change to her contact, presumably. She doesn't have to agree to it. They can enforce it though, but only after giving her the contractual notice and then re-engaging her on this new contract term.

Whether she is entitled to sick pay is another matter. What are the sick pay terms?

If the reason for the change is due to her health, and her health issues amount to a disability, then it does sound like discrimination. But, is it a disability?
I'm not quite following what you said about them wanting to be more flexible - was this for when she felt like it, or them? Your wording in that section is a bit difficult to follow.
So, given that, we don't know currently if the reason is the ill health anyway.

A month off already in five months isn't great though, they might let her go for that itself.

Well they can’t unilaterally change her contract but given she’s short service they can dismiss her with notice (probably a week unless her contract says otherwise).

if her anxiety is long term it might be a disability, but having 1 month off sick out of 5 is unlikely to be a reasonable adjustment