CB ESA after receiving maternity allowance

Hi
My daughter was put into the support group for contributions based ESA for 18 months in January this year. However, because she was pregnant she went onto maternity allowance in July. (Her employers would like her to return and are happy to keep her job open till the end of her maternity leave, though she has not received any pay since December last year.) Should she be unable to return to work next year because of her disability, she will need to reapply for ESA. She cannot claim income based ESA as her husband works more than 16 hours a week, though is on an extremely low wage. I thought that national insurance contributions are paid for someone receiving contributions based ESA. so they would continue to qualify for it as long as they were still disabled, but something I read recently suggested that they can only qualify if they have actually been working in the previous tax year. If that's the case, my daughter, and anyone in a similar position, will be unable to claim any benefit, apart from PIP, a year or so after they have to stop working. Is this really the case?

Following on from this thread please clarify. What does this mean if someone who has been on IB since 1999 then transferred to ESA SG and stays in this group, without a break until they retire at aged 66 as a female ( born 1957) in 2023 under the current legislation. Will they receive the fully topped up Retirement Benefit ( Old age pension) or will they be at th disadvantaged amount etc. Or are we looking at a scenario not yet designed for public discretion. Women especially have been turned gated upon from the govt who were born between '53-'64.

Hi Gordon. Thanks for your reply. If I've understood it correctly, someone on ESA (CB) for a full year would get 50 weeks of NI credit and this would qualify them for ESA (CB) the following year. And that would continue in subsequent years if they continued to be so disabled that they remained in the ESA support group. Is that right? I know ESA is only paid for a year if you're in the WRAG.
Sorry to be needing clarification on what is probably a very simple point but I need to get this really clear in my head. Many thanks.