I thought you would have been a little heavier than 17st and a tad over, maybe I'm a little taller than you at 6ft tall.
I'm finding that 2st make a really nice difference when climbing and probably the lightest bike in the world would not have come close to offering the benefits that loosing 2st made to my cycling

even riding my heavy MTB feels easier now.
Soon I should be changing my avatar
I hope you meet your target before your holidays.