When I coordinate with someone they tell me what time they are going to drop the ADR. Say for instance it's CRT, I would then go sign into
MDE a few minutes prior to dropping time to make sure I am logged in, I would go specifically to CRTs page and enter in the time the reservation is for and the number of guest the reservation is for and then when the time comes that you guys agreed to drop it at I would continue to hit refresh until the time pops up and then you grab it. I would also make sure the time you guys decide to drop it at is at an odd time like at 9:57 or a time where most people wouldn't be online that way you won't risk losing the ADR. Say for instance someone post at 10:20 they have a cancellation, don't make the drop time at 10:30 as people would know it's going to be dropped soon and may look for it so they can grab it themselves. Hope that helps you