Thank you for contacting Synology.
I can assure you that we are not in violation of the General Public Licenses as there no stipulation on 'when' the source code for newer versions of DSM have to be released,
only that the open source parts must be made public.
To that extent, we are fully aware of our obligations and at this moment in time I do not have a precise date to provide you with.
I can only advise you that once the source code is released it will be made available via our usual open source project locations e.g.
https://sourceforge.net/projects/dsgpl/