If you get accepted the training will be at the new college which is at the CTC.
There are many reasons.
Economic situation has reduced demand for ATCOs.
College move getting in the way.
Swanwick is just in the process of moving to IFACTS, until that system is running properly and all the OTJIs feel competent enough on it to mentor, there will be no more trainees there. Since 80% do radar and the majority of them work at Swanwick, I'm guessing it to be the main reason. Note the word guessing though