Finished with help of several nudges from this forum. Despite having lived a couple of years in 5d I hadn't a clue that 8d was local. I got the 2nd word and then a PDM.
FOI: 25a
LOI: 17a
COD: Possibly the clever 27/6, though it's the sort of GK I don't have. The whole puzzle had too much GK, I thought, and my sympathies go to non-UK solvers!