Units used for training on my course (at least for ADC - nowadays ADV/ADI - training) were all NATS units plus Ronaldsway, Oxford and Jersey; I don't recall anyone off my course being sent to Leeds but I could be wrong as it's nearly 50 years ago.
You can add Luton to that list, I was on 28 course and did my Aerodrome validation at Luton in 1973/4