Ta.
I was primarily concerned that it changed at the same time that I changed mirrors, the concern being that it was caused by something that I had done. Your reply lets me know that it's a global change.
It seemed to go ok (even left my version of XF86Config-4 alone!)
I've not noticed any difference over the older version, tbh, so I'm not going to upgrade it, 3D isn't something I've got to worry about on an ancient TP600 laptop.