Article 77 is just making this explicit: You complain where you are living (even cross country!), where you work or where the suspected violation took place. It doesn't say anything more.
Indeed I am exploiting that option. I have lost confidence in my country of residence. The EDPB reports show that most DPAs are understaffed and up to their necks in work. Germany was an exception. Germany has far more resources for GDPR complaints than most of Europe.
Because of this there is no standard form to fill out: it depends on the agency itself where you choose to enter your complaint.
So Germany does not have a nationwide form? Each of the 17 agencies have their own? I guess I have to work out which region I am dealing with first.
But before that, I need to know if the federal agency is who I am working with. The data controller referred me to the Federal agency, but that seems off.. from what I have read, the Federal agency is just a single point of contact for the EDPB. I see nothing about the fed handling GDPR complaints.
(edit) I found the relevent region. I think I’ll distrust the controller’s referral to the federal office and use the regional. Which has its own form.