Headers not updating when on `insertSections`

[MilanNosal]

Hi! Great work!
I am using the layout and custom ShelfElementKindSectionHeaders. However, if I try to later insert a section using insertSections, while the content of the section animates in, the headers stay the same resulting in inconsistent view.
E.g., If I start with this:

A
a a a a a a
B
b b b b b 

and insert section C with c c c c c at the beginning, it ends up looking like this:

A
c c c c c
B
a a a a a a
B
b b b b b

If I scroll away and come back, it shows correct data, so it really looks just like an error with the animation/insertion itself. How it should look right after the animation:

C
c c c c c
A
a a a a a a
B
b b b b b

BTW calling reloadData works as expected.

Any idea what might be wrong? Thanks