You have to modify the array referenced by other_array.
Variable assignment doesn't achieve that.
For a simplified example:

a = [5, 6]
b = a
b = [3, 4]

The value of a won't change in the above snippet. Because you just reassigned b to something else.
You have to use array modifying functions in order to change the underlying object instead of creating new ones.
For example:

a = [5, 6]
b = a
b.clear
b << 3
b << 4

This will change a to [3, 4].

It's intermittent for me, but when it happens nothing seems to go through (other times its just slow)

It's been like that for at least a few hours today.