I took it to mean that people were calling in threats that people IN Q shirts were gonna do bad things. And that is/was a way for the derps to suppress the people from wearing Q shirts. They got the SS to disallow Q shirts. Derps win.
(partial Q post
Why, before each rally, are 'threats' now being called in re: 'Q' attendees [effort to prevent ]?
Just my take.
Okay, your take makes more sense.