Flax and oatmeal soaker: revamping my entire process

Hi, for this bake I decided to completely change up my process. I did this in part to fit my schedule, since I decided to make the dough late at night on a Friday, and in part to try a longer bulk ferment and baking the loaf straight from the fridge. Oven spring wasn't as strong as in my other bakes, but it might've been due to 1. a sleepy starter, 2. an overly long bulk ferment, 3. shaping and proofing in a bowl as boule, instead of making a long batard.

Ingredients

240 g KAF AP flour
30 g KAF WW flour
30 g Arrowhead Rye flour
200 g water
6 g salt (1.5% salt, lowered to adjust for salinity from olives)
0.5 g IDY (roughly a pinch, to make up for the slow starter)
70 g starter (fed 8 hours prior with 3:1:4 AP:WW:water)

Soaker

10 g oatmeal
10 g flax
10 g bran
26 g hot water (78% total hydration)

Levain build

50 g starter (100% hydration, fed 1:1 starter to feed 8 hours ago)
10 g WW flour
10 g Rye flour
20 g water

Steps

1. Feed starter, autolyse flour and water, autolyse for 1 hr
2. Fold in starter, salt, and soaker, rest for 15 minutes
3. 100 french folds
4. 5 sets of S&F in 30-minute intervals
5. Bulk ferment for 5 hours at 66˚F (I decided to go to sleep, this was 1am- 6am)
6. Shape then proof for another 40 minutes
7. Cold ferment for 10 hours
8. Preheat DO and oven to 500 F, line bottom of DO with foil, leaving one corner folded up
9. Score and load loaf with floured baking paper straight from the fridge
10. Slip 3 cubes of ice into DO, ideally under the folded-up corner of foil
11. Bake at 475 F, covered, for 25 mins
12. Bake at 425 F with convection, uncovered, for another 20 mins