From past discussions I am aware that these must needs be not overlapping in time / day but that two profiles can be created for Provider O,P such that anyone seeing their profiles immediately knows their availability at each location while Provider Q,R would only require a single profile.
Given this, what Google accounts should be creating these profiles? The same as the GMB account seems to be the wrong answer. Is it preferred to use an account the Providers have used in the past or can it be new Google accounts created specifically for this purpose? Finally can the accounts used for Provider O,P create both of their profiles to be linked to their respective locations / schedules?