I don't know anything about the legislation but both my grandmothers worked full time from the 1930s to the 1970s when they retired.
One granny used a wet nurse and a nanny as childcare.
Tragically her baby son died in the care of a wet nurse.
As far as I know the baby lived with the wet nurse in the nurses home.
I never got to ask my granny about this, but I'm guessing some of her motivation for this was her need/wish to work and the absence of maternity leave and the child's need to be breast fed. But also perhaps the fact that her 26 year old sister was dying of TB, she might have thought she was protecting the baby by sending him away. I wonder if her baby actually died of TB too. She was a teacher and avoided the marriage bar by swapping jobs with her sister.
The other way she managed child care long term, was by her husband working nights all his working life. So he was there for much of the day to deal with kids etc.
My other granny ran her own business as young widow with 6 small kids, in the 1940s.
She employed 2 household servants who did anything and everything, including childcare. Neither of these women ever had children of their own and were always like grannies to me and had a special place for my father in their hearts and homes.
One of those "servants" remained living in my family home until she died in her late 80s.(she had retired for decades!!!)
She was more like my granny at that point and my daughter is named after her.