Vet has now seen mum and pups, says mum does have milk but she's only really letting it down in her front teats and not her back, but that there is less milk there than when she saw her on Monday. She's given her another oxytocin injection and advised me to keep up the warm massaging of her back teats.
She's given me some pro-biotics for the pups just in case the antibiotics they are on have disrupted their ability to digest food properly, but she didn't seem unduly worried about them (I think I do enough of that) but agreed a little bit of supplement milk wouldn't do thtem any harm.
Thank you to everyone for the suppport, I have done all this before but it's nice to know there is support out there.