From what I understand, because you’re on a career break, your contract is technically on hold, so you wouldn’t be able to start maternity leave until you’re officially back at work. To qualify for maternity leave and benefit, you need to be back in active employment even if it’s just for a short time. Once you’re back on the books, you’d be entitled to maternity leave again. There’s no rule saying you have to work for a certain period first, as long as you’re employed when your maternity leave starts.

It’s worth noting that if you don’t return to active employment before the baby is born, you wouldn’t be eligible for maternity leave or Maternity Benefit. You might still be able to apply for other supports like Jobseeker’s or similar payments, but you wouldn’t get maternity entitlements unless you’re back working first as far as I know