Thanks Scan (and DPD), my order just arrived in the expected window. Please refer to the attached picture of the 900D box. The damage looks minor and does not appear to penetrate to the case so my wife accepted it.
http://forums.hexus.net/members/bugb...box-damage.jpg
Just being a bit paranoid here based on reports of deformed cases on some review sites. Although these were pre-release samples and Corsair did mention they would be impoving the packing.
Although the box damage is minor there is a chance it was caused by a hard knock which may or may not have any impact on the case structure. Hopefully it's all fine but wanted to report it early in case it needs to be raised with the courier.