Django All-Auth Role Based Signup
@pennersr was kind enough to answer this on the allauth github page:

This truly all depends on how you model things, there is nothing in
  allauth that blocks you from implementing the above.
One way of looking at things is that the signup form is not different
  at all. It merely contains an additional switch that indicates the
  type of user account that is to be created. Then, it is merely a
  matter of visualizing things properly, if you select type=employer,
  then show a different set of fields compared to signing up using
  type=developer.
If you don't want such a switch in your form, then you can store the
  type of account being created somewhere in the session, and refer to
  that when populating the account.
Having read many stack overflow questions, tutorials etc on all-auth I keep getting the impression that it only supports the registration of one type of user per project.
I have two usecases

A business user authenticates and registers his business in one step.
A developer user authenticates and just fills in the name of his employer (software company).

I do not want the developer to see the business fields when he signs up. i.e his signup form is different.
If, in fact signup should be common and the user specific details should be left to a redirect, how to accomplish this from social auth depending on user type?