I had a similar thought - my HR has confirmed that my enhanced pay stops as soon as I end maternity leave. So I’m waiting until my enhanced pay ends naturally in July to start my SPL.
It does yes. Have a look at Teacher's SPL for guidance. I will be forfeiting some of my 12 weeks enhanced half pay in place of SPL full pay during the summer hols as this was more beneficial money wise - as after that it just goes to statutory for me anyway. There's a video on Teacher's SPL website
Yes. You’re better off waiting until enhanced mat pay is finished before taking any SPL, once you take SPL it curbs any enhanced pay and you go down to SMP straight after