Multiplayer Playmode Slow to Open Second Editor Instance

[wanton dune]

Using the multiplayer playmode package v1.6.3 on unity 6000.1.17f1 and when launching a simple scenario of just the main editor and one editor instance it takes 30 or more seconds to launch and be ready.
Have done a profile and a lot of it seems to be from the initial frame of the editor instance opening taking ages(image attached) and was wondering if anyone else has experienced similar issues or know of solutions.
A test was briefly done on 6.3 and load times seemed to be similar to 6.1

[limber dock]

Do you already have the clone window open? Honestly, 30 seconds to open a 2nd editor is pretty quick. 30 secs to start playing after it's been open is a bit excessive.

[wanton dune]

The clone window was not open.

Sometimes it can take ~45 seconds or up-to 1 minuet, but even 30 seconds can become frustrating if they get launched a lot due to frequently stop/starting playmode to make/test changes.