Um, well an employee where I work was dismissed for poor attendance due to sickness and they were advised they could by the HR company they employ for such things, I believe the employee spoke to ACAS too, but they had a bout of flu that brought them low and then caught everything going after that, and triggered the sickness policy, we work with very vulnerable people, so you'd think that our employer would be shit hot on people not going to work with any sort of illness and supportive when taking time off to protect the people we look after. No, they punish you for doing so.
I'm still in touch with her, she doesn't get past the application or interview stage where "Why did you leave your last job" comes up.
While policies like that exist, are allowed to exist and are supported by legal framework, it's not going to change. Of course she was assumed to be 'taking the piss' which seems to be the standard response in low paid roles, despite the fact most only offer SSP (which is about a 1/4 of my wage) for sickness, there's very little incentive to 'take the piss' when that's the consequences.
And unfortunately many (especially low waged places) are like this, moving between them doesn't really achieve much in the way of better treatment.
Just a question but you mentioned childcare, is that a nursery? Do they pay enough for their staff to make provision for any absences they may have due to illness and also have a policy that doesn't punish them for taking time off sick to protect the children?