What would you do if this happen to you??

[williamhha]

should buy a brand new watch if so particular about the cosc, lower a bit on the expectation if buying a used watch.

[red_parrot]

time send the watch for servicing

[minerva]

he check it with a timegrapher?

[Trinidad]

Irritated to deal with people so anal.
They better just go buy a brand new watch from AD.
Even so , there is no refund if it is not COSC.
At most they retime it for buyer if under warranty.