I called today (July 18) about my 70-300IS, serial number 090xxxxxx. After navigating their phone menu system, I got right to a live person.
However, it was obvious that he did not know what I was talking about, and had to look things up. Not a big problem. After several waits on hold, he set up the repair and told me I should receive a shipping label, and that it would probably be second-day air. He expected turnaround time to be 7-10 business days.
I'll see what happens.
Edit: Later on July 18 I received a call from a Canon representative. He promised to email instructions for shipping, and (more important) an email I could print to get a prepaid shipping label. He also said that the repair would take 7-10 business days, and that shipping would 2nd day air in both directions. And he said that they would be repairing, not replacing, the lenses.
So far, so good!
Canon 80D, 60D, Canon 10-22EFs, 15-85EFS IS, Sigma 100-400, Sigma 135/1.8ART, Sigma 30mm f/1.4DC, Canon 60mm EFs Macro, Rokinon 8mm fisheye, 550EX flash, Olympus TG6 underwater P&S
Postprocessing: DxOLabs 5, DxO Viewpoint 3, Paint Shop Pro 2021
Speak softly and carry a big zoom.