Some great advice from others here.
One thing I would say though, if he’s out of the house 8-6.30 you’re not “the breadwinner”.
You may be the higher earner but you are downplaying his role in working and bringing in a wage, so be careful not to crush his spirit entirely when you talk about him cutting back his hours to facilitate you.
It’s not a gendered thing, for anyone working long hours, regardless of whether or how much they earn, they want validation that their work is valued.
You will get a better response from him by valuing the contribution he makes than by belittling his work because it doesn’t pay as well as yours.
Even as a SAHP it’s hard to hear that your work isn’t valued. For someone who’s out of the house for a full day it’s just insulting to be told they’re not the “breadwinner”.
I do think you should go for it and buy in help where you can to make both your lives easier but you also need a frank conversation about what he brings to the table at home and about contributing equally in any way you are both able.
It might be that your new role includes some travel, in which case he will need to step up with the parenting. There are breakfast clubs, childminders etc to assist with school run, but that shouldn’t be INSTEAD of him pulling his weight, but as well as.