Upon retirement, what was your number one source for reemployment (network of peers, social media sights, career fairs, hiring events)?

Peers

My wife was still active-duty when I retired. We PCS'd twice and I had to job hunt twice. Both times I got hired from companies I found at job fairs. In fact, from the second job fair, I had multiple interview opportunities.

I used all of them even a few hiring conferences hosted by veteran recruiting companies ( Orion, Bradley Morris are a couple). Went to a conference Bradley Morris was hosting in Atlanta and was eventually hired by the Toyota plant in Mississippi for a maintenance position. Still there 4 years later. Closest job I could find to working on the flight deck. I still look forward to going to work