For anyone currently doing planning on non-labor resources and roles in cost plans that use the Populate feature, please do make sure testing is done particularly for this (excerpt from the cookbook):
However, if cost plan population added a row previously (pre-14.1), the row is deleted during cost plan repopulation.
this means specifically -
If in a pre-14.x version you have a cost plan that was populated from team/assignment, and there is a row brought in by population (not manually added) for your non-labor resource or role, even if you have then manually entered Planned Units and/or Planned Cost on this row -> on 14.1 if you enable the option to skip non-labor and populate this same cost plan, that row will be deleted/wiped out.
The removal of planned data on a row that was previously created by the populate action when a match is no longer found during populate, is not new