John,
My guess is PG Music was contacted by Notation Software Germany with questions regarding how to integrate Band-in-a-Box styles into the Notation Software product. PG Music provided the plug-in to Notation Software Germany. It became Notation Software Germany's responsibility to integrate and publicize the feature. PG Music may, or may not be aware Notation Software has released the feature.
Here is a quote from Notation Software that explains the plug-in:
The plugin for notation composer has been developed by PG Music Inc. and incorporated into notation composer 3 by Notation Software. Combining the accompaniment technology of PG Music with Notation Software provides the following benefits:
* notation composer transcription technology is used to transform the Band-in-a-Box® generated accompaniment into sheet music.
* The Band-in-a-Box® plugin comes with a package of 150 Band-in-a-Box® styles. Any other Band-in-a-Box® style file either from PG Music or any third party can be used.
* .not files generated by notation composer with accompaniment from the Band-in-a-Box® plugin can be opened by notation musician, notation player and another notation composer without Band-in-a-Box® plugin.
* notation composer contains a trial version of the Band-in-a-Box® plugin with 25 styles which expires after 60 days. A purchase of the full plugin package can be done any time.
While performing a quick look through of the Notation Software forum the question of integrating Notation Software and Band-in-a-Box was first asked in 2012. Software Notation announced a software development agreement between the two companies in November, 2016 and internal alpha testing began in December, 2016. Beta testing began in May, 2017. I'm not sure when the feature was released.
Here is a forum quote regarding availability:
From a distribution concept we will distribute the Band-in-a-Box Plugin (BBPlugin) with every Composer trial version and every Composer full version as a trial package. The trial period for the BBPlugin will be 60 days which starts counting when the Composer 3.0.7 is installed either as a full purchased version or as an update. In these 60 days the Band-in-a-Box feature is 100% available for everybody and can be tested thoroughly.