ricky1 am suffering similar issue to you, all new kit but seem to be snapping chains.
Improvements so far have included ditching XT double to SLX triple, replacing a slightly bent RD hanger and fitting RARr cage to XT clutch RD. Had thought that would be it but with the last near snap noticed play in BB so not sure if this contributed to issues but will swap spacer to non-drive side when replace.
Running out of ideas. Good luck with yours.