This is a little confusing to me, but I'm still sick and doped up so maybe you can make some sense of it:
According to pages 353-354 of the discovery documents, all the way back in the beginning, there is a property sheet with the laptop on it and the only date on the two pages is "Reported: 7/15" I would imagine that they would take the laptop as soon as possible, but I wonder if this is the date the crime was reported. The following two pages of discovery, 355-356 has only one date also: "Reported: 7/16" so maybe a typo or maybe the date the items were taken? The signatures for Chain of custody are still blank on these sheets. This may be a starting point if not the answer. A lot of other things were taken at the same time.