Your BP should have said Skyteam Elite Plus on it. That is what allows you to board with the D1/J cabin. The whole point of that Skyteam level is so that these employees don't have to be trained on all the various status levels of the Skyteam partners. Went through both AMS and CPT twice the past weekend and in every case they boarded both D1/J together with Skyteam Elite Plus. It did say Zone 2 on my BP, but they all boarded 1 and 2 together at the same time. So what you really have is a case of an employee not following this Skyteam standard.
That is incorrect due to the new boarding zones DL came up with that debuted last week. DIAMnd is what prints now not PREM etc (my BP does say STE+ too)
If my boarding pass just said STE+ then that means PM and GM would board with D1 too
https://www.delta.com/content/www/en...-priority.html