Rooting Mulberry cutting

After my spring grafting I’ve noticed this 2024 Spring Grafting Thread - #681 by Tana happening and then my nigra cuttings literally cooked in the ground. And I had an idea to try and see if I could get that root-like callusing on a nigra and then try to root or air-layer it.
In early July I made diagonal cuts into some pencil-sized branches and wrapped them up in self galvanising rubber tape. . When I checked them in August, they all callused neatly, but I found an extra one today as the tree has almost defoliated. It had a lumpy callus.


I’ve air-layered it but I don’t know if it would last outside even if it roots before frosts. (No idea when that is happening this year)
Should I snip it off and put in wet perlite indoors?

I am repeating the experiment next spring before budding.