The bombs were not planted at 11:14, during the 'tape change'. Some e-sleuths have been pretty sure they see them around 11:00. Regardless it wasn't then.
They didn't go back and sit in their cars. They leave and come back. That's when Eric talked with Brooks if he did so, not before. They didn't sit in their cars then either. I very much doubt they planned to shoot from their cars for several reasons. There's no evidence the starting on the stairs wasn't plan A.
Go Go might have been students telling people to run, rather than either perp.
The first shots were likely when Patti and Brian came out, telling them to "knock it off", then Rachel and Richard. It had to have been before Dylan descended the stairs.
Eric killed Daniel Rohrbough, not Dylan.
And I don't think either bomb was set for 11:17. I think the facts make more sense with a first bomb at 11:20, and the second bomb at 11:35 - hence at 11:35 they stop killing, at 11:36 they leave the library and by 11:37 are back to tossing pipe bombs into the cafeteria like they were when they entered the school, on top of several other reasons. The only source for 11:17 is Dylan's (contradictory) notes, not from reading the clocks on the bombs or some physical evidence.
Subject: Problems with the Jeff Co timeline 
Sun Sep 20, 2020 5:20 pm