I have some 2015 and 2016 UK coins for circulation and it appears that the Jody Clark engraver mark (J.C) is smaller for 2015 and larger for 2016 (for penny, 2 pence, 5 pence, and 20 pence at least).
Does that difference apply to 10p, 50p, pound, and 2 pound as well? Is the 2016 size kept for 2017?
Attached are 2015 and 2016 images of 20 Pence coins taken with no camera adjustment in between.

