Just checked the frequently asked questions section of Play.com and noticed the answer shown below, maybe the reason why it has changed to Processing!!
My order was shown as â€˜Postedâ€™ but has reverted to â€˜Order takenâ€™, â€˜Processingâ€™ or â€˜Packingâ€™
Very occasionally an error or an incident occurs at the point of dispatch that means we know that the original item is unlikely to reach you. If this is the case, rather than waiting the usual 14 days to be sure that the item has gone astray we prefer to â€˜rollbackâ€™ your order and process it again.
In these instances it is possible, rarely, that you may receive a duplicate copy of an item, although you should not be charged twice. If you do receive a duplicate please return it unopened â€“ see our Returns policy for more information.