Are there any special risks associated with filing a bypass continuation-in-part application?

Yes, in some circumstances, a PCT application can be considered prior art against any claims supported only by the content of the subsequently filed bypass continuation-in-part application.  PCT applications are normally published 18 months after the earliest priority date of the PCT application.  The danger stems from attempting to file a bypass continuation-in-part application more than 12 months after publication of the PCT application.

Jean McCarthy of Quinn IP Law describes this situation in more detail.  The link is provided below:

www.quinniplaw.com/bypass-continuation-versus-national-stage-entry/