Yes, the whole reason for the issue is my need to change milk supply, moving over to a local diary (P&H) rather than supermarket (P only). With the local milk, the curds are so bad, and the CaCl has almost no effect, even at ridiculous concentrations. The supermarket milk produces reasonable curd, and even though I always add CaCl, I've never been convinced that it has made a difference. I still get a degree of shattering, but I can live with it. Culture is ok - I did a side by side test with the two milks.