Look on your local council website to see what child care provider s are able to assist you. It took me 7;weeks to get child care in place so be warned. The council will have a free list . Do not use these so called childcare website s they are full of strange people who are just running a business plus you will need to pay to correspond with them .
there are childminders who take children overnight…obviously your children would need to spend some time with them etc first. I imagine the cost paying for children to be cared for all night would be high. my child minder used to look after a little girl who’s mum was single and did 12 hour nights as a prison officer. mum would pick her daughter up from school, do tea, play homework bath and pjs. then drive her over on her way to work and pick her up I the morning. she did 3 night shifts? money was better and no real time lost with her daughter. I don’t know how she funded it though. the other option is someone coming to sleep at your house with the children but that would involve a massive amount of trust. is there anyone you know who would be trustworthy, doesn’t have commitments of their own and would appreciate the money? or a family member that would help you (even if it’s your ex partner’s family they may do it for the children)