Cryptic crossword No 438

Bluejacket goes above and then beyond / A grid of true distinction hast he spawned. (Brilliant! Particular love for 1d, 13d, 14a, 17a, 18a.)

Thanks Bluejacket I enjoyed this. Clever clues and I liked your definitions, like Tug I thought 14A, 18A and 1D particularly good. 18A being my favourite. There were a couple I couldn't quite fully parse, annotations would be helpful. Couple of spoilers in reply.

Bloody amazing.