Firstly, I’m enormously privileged to be asking this question and it’s definitely a FWP.
My DS is 13 months. I came back from maternity leave when he was 8 months (just before Christmas) because my maternity cover had gone tits up and basically, if I didn’t come back and steady the ship I wouldn’t have had a department to come back to.
Anyway, I negotiated to come back on 4 days and for my full time wage to go from £44k to £60k, so that on 4 days I would be earning £4K more than I was on 5 days. I also negotiated to work 2 days from home and 2 from the office. I was in a strong negotiating position, they needed me more than I needed them and so I got what I wanted.
Anyway, my role since I came back has expanded and I’m finding im working very late most evenings. I’m doing 40 hour weeks on a 28 hour contract. no overtime payments obviously. I’m managing this by working after DS has gone to bed mostly and I’m knackered! The business has approached me and asked how I’d feel about going back to 5 days given I’m doing over 5 days hours anyway, but I would be working every day not compressed hours.
Im very conflicted. I LOVE my time with DS, however cost of living is creeping up and we’re starting to really feel the pressure now. We are getting by on my £48k plus the money DH earns from a bar job he does 12 hours a week (more for mental health/ none baby time than money) but it’s getting tight.
DH is a stay at home parent but has offered to get more hours. The problem is his earning potential isn’t great, so the cost of childcare would swallow his wage (hence why he stays at home) so if we want more money, realistically me going to 5 days is our best bet.
For reference we can afford the day to day, we are not freezing or starving but we’re being careful with treats and extras and were currently not saving anything.
DS will be our only baby for reasons I’d rather not go into.
I just feel like if it was the other way around and I was the SAHP and DH was working then it wouldn’t even be a question. It’s because I’m a mum that I’m feeling so guilty about the prospect of going back full time and sacrificing time with DS 
WWYD? Would you go back to 5 days and give up time with DC in order to relieve the financial strain a bit? Or would you stay on 4 days as long as possible and just be a bit skint for a bit?