This literally just in from IDPA HQ prior to Nationals:
The Rulebook Clarifications for Q3, 2014, have not been finalized for publication. We would like to publish this completed update for those of our competitors who will be attending IDPA Nationals. Since the CZ Custom Shop is not an OEM (Original Equipment Manufacturer), the CZ SP-01 Accu-Shadow will not be deemed SSP legal, based on the following rules in the current rulebook: 18.104.22.168.1.
Competitors planning to shoot this firearm at the IDPA Nationals will need to make other arrangements. Please see Robert Ray for more information on borrowing a firearm if needed. Comp-Tac has generously offered to lend holsters for borrowed firearms and HQ has an assortment of SSP legal firearms to lend for the match. Any competitor who arrives with an Accu-Shadow and chooses not to shoot the match will have their entry fee refunded. We understand that this is a major inconvenience due to the late nature of this decision. We apologize and are striving to fix our process so that this will not happen in the future. We thank you for your understanding.
Executive Director, IDPA
We are publishing this so that anyone attending IDPA Nats and planning on using an Accu-Shadow in SSP has access to this information and hopefully has time to make alternate plans on what gun to bring with them to the match. For reference, the rule cited states:
22.214.171.124.1. Externally visible modifications other than those listed in the Permitted Modifications
Essentially, the Accu-bushing is what knocks it out of SSP. Again, this information is being published so that shooters planning on using an Accu-Shadow will have an opportunity to get a different gun.