The prototype Chipmunk, CF-DIO-X flew at Downsview on 22 May 1946. In November that year, it was shipped to Hatfield for testing and demonstrations. It was re-registered as G-AKEV on 28 August 1947.
There is a very good article on the early Chipmunk history here:
Top of the Class - page 1
However, the article does not mention what happened to the prototype (although there is a "To be continued" footnote on the last page). A search of the CAA database shows that it was struck off the register in 1951. Does anyone know what happened to it?
Incidentally, in the same article, there is a detailed description of the Fairey Primer, which was competing for the same contract as the Chipmunk. I'm glad the Chipmunk won. The Primer is just ugly!