Blackphone CTO prides of their transparency while stating they will never “release” all their code for review, nor tell their customers when a critical bug may have been discovered. Also, they do not even mention firmware or hardware schematics, nor they clarify which code form third party they use that will not be available for review:

I welcome any and all discussion but the immutable constraint is this: we will do testing, we will publish a Transparency Report reflecting an honest view of the results, and we will use this data as evidence of due diligence in support of our objectives of security and privacy.

It doesn’t mean we can share absolutely everything, and it doesn’t mean we’ll release information the instant we receive it. For business or other reasons we may choose to hang onto certain things until after we’ve implemented fixes, but our Chief Security Officer’s team will be responsible for managing this line of communication and keeping the world informed of whatever we can share.