contact csa - tell them the ex has said the kids are staying with you for the next 4 months, except for every second weekend.
Yep - contact your laywer
As above... Call CSA today if possible... No point stressing over if she may or may not pick up kids from school.... As I wrote previously, all this erratic behavior and to and fro with the kids on her part is definitely causing the kids psychological harm...
SPEAK TO YOUR SOLICITOR about involving child services to pay her a visit.. It will all be materiel that you can use in court to prove her crazy behavior and the harm and distress she is inflicting on these kids... Not having a car is NOT any kind of excuse..