After over four years of fighting, including numerous regular phone calls to a variety of case workers and three letters to my MP, yesterday I received five (yes five!) letters from the CSA to say that DS's dad has been re-assessed and DS will soon be getting the maintenance that he's entitled to.
There were so many times I felt like I was banging my head against a brick wall and questioned many times whether the stress of chasing the CSA was worth it, but it was. I feel triumphant!
Apparently they will send a letter (probably five!) soon to tell me when to expect payment to commence. Just hoping Ratbag pays up now, or I'll be back to sqare one again!