RoP Snatch Weight

I just started my first week of the ETK RoP and wondering which KB size to use for my snatches. I did the PM for 6 full weeks and used a 24 kg bell for all swings and getups (well, except for the first 1-2 TGU sessions when I used a 16 kg). I’m also using the 24 kg bell for the C&P ladders in the RoP without much difficulty as well. So I thought I’d just snatch with the 24 as well, but after the first couple of reps I felt it was a bit too heavy for my grip. I dropped down and used the 16 kg for the snatch session, but that felt that was a bit too light and I thought my form started faltering accordingly (getting a little wild with a "loose" arm). However, a snatch is a snatch and I definitely felt the conditioning work over the course of the session.

I don’t have a 20 kg bell, which I think would be ideal. In this scenario should I use the lighter bell for many more reps or use the heavier bell for many sets of low reps (meaning more rest during the session) and increase as I go along? Since the snatch test ultimately calls for the 24, I’m wondering if I should just start there and build up even if it means resting too much in the beginning. Thoughts?