Part -time work would pay more pro-rata than Supply and you would know where you are with childminding arrangements. You would also get sick pay, maternity pay, access to Teacher Pension Scheme…. Also, your career would still be ongoing. It’s a lot of work to juggle though. You could get Carers Leave if your child is registered disabled.
The advantages of Supply Teaching are you can drop everything in a crisis guilt free. Also, if you’re in a horrible school you can leave and never have to set foot in there again. And, if you’re not good at interviews you don’t have to worry on the whole. Disadvantages, - childcare, low pay, uncertainty, lack of respect from some permanent colleagues, being out of subject, in different key stage,…Usually the only available work tends to be long term and then you have all the work but stuck on M1 until Week 12 when you get paid the same as if you were a new permanent employee of the school. (Most placements don’t last long after Week 12.). Day to day work sometimes pops up but it’s very sporadic. Often paid less than M1 even at so-called Teacher Rate. If you’re willing to accept Cover Supervisor rate (half M1) there might be more day to day available. The other big disadvantage is there are very quiet times usually Sep-Oct and Summer. It makes childcare arrangements difficult.
I was in the same position about 20 years ago, so a bit out of date. I had just accepted a part-time post. I stuck it out for a year but it was too much. I left and became a SAHM mum for a few years but it was good to feel it was my decision. The childcare costs ate up all my salary but there may be more subsidies now.
I think you have to go with your gut feelings. Be aware you can change your mind and your arrangements from year to year and that’s OK.
Good luck. Things do get less hectic.