SSA Job: Second set of references contacted. What might this mean?

May 28th I took a 1.5 hour exam and had a one hour interview. The weeks of June 9th and 16th, 3 of my 6 provided references were called. July 1st, they asked for an unofficial transcript or diploma to verify I met minimum qualifications. Unfortunately, I don't have my diploma yet so I had to submit my transcripts, which shows I failed some classes start of COVID. My GPA was not the greatest - a 2.5. Today, another of my references let me know he was contacted by the department again today for a reference check. I am concerned about what this might mean and why there is just so much going into this for an SSA position. Does anyone have any idea of what this might mean, and how important GPA is in the grand scheme of things. For additional context, I graduated from college 3 years ago and have been in roles with the same company for four years now, a job I got before I graduated. How important is GPA? Why are they calling the second set of references I submitted now?

Edited TLDR - four and a half years with two promotions from a base role to lead to business operations analyst. My first three references were three managers I worked closely with, one for the entire time I’ve been there. After contacting the three managers about three weeks ago, they started contacting the final three references just now. Scared GPA might be the reason.