Looks like 2:53 is an important gateway moment when passage is allowed between the worlds not merely in a singular instance.
Cooper Cooper was the message Briggs received at the listening post as recounted in the Frost book.
And now the connection has been made. On the print out from the messages Cooper Cooper. There are two Coopers and Briggs knew it back then.
In S2 there were 3 "Coopers" on the printout. In tonight's episode the third was seen torn off. Was the 3rd Cooper the original Dougie that got sucked back into the Red Room?
Yes, and on Briggs' note inside the metal canister he noted that the important location for Bobby to find was 253 steps from Jack Rabbit's. Or 2:53. Nice.
and the clock on the dash board of the car of Bad Coop was 2:53 when good coop got out