5 hours ago, Anna N said:Just to be clear the vacuum is used to autolyze the flour and water (and yeast) not to mix the dough.
I may be wrong, but the heading of page 3-108 reads: "How to Perform an Autolyse (and Mix) by Pulling a Vacuum on the Dough". And in step 6, removing the dough from the bag, they say: "The gluten is now practically developed."
The last step is stirring in the salt.
Edit: I'd be inclined to add the salt initially along with the yeast and such. Then after initial mixing divide the dough in half and bag each separately. Vacuum each bag and retard one in the refrigerator while continuing to ferment the second.
