257 was Cat4 at St Mawgan. Once repaired on site, it was ferried to Woodford, subsequently declared Cat5 and sat outside for years until scrapped in the 90's
AFAIK. It was not one of the 11 Aew3's - that project ended in 86 round about the time257 would have made its one and only flight post-fire.
249 was another that apparently had underfloor burning (without being destroyed) after being back converted to R1 (to replace 666).