I think Ts view connection as important especially for the comfort of the client. I wonder if part of what the side by side seating is more difficult for her is that also a big part of therapy is being able to read body language and facial expressions?

EMDR T is getting pretty good at assessing when I am starting to disassociate based upon my body language. She cant explain the difference but she definitely has helped me stay present the last couple of times.

T used to be able to read my facial expressions to tell when something was bothering me but I was not telling her.

So I wonder of this might be why your T is supporting you by sitting this way but hoping in a few weeks you can return to the other way.