Note to those using HOI 4 schedule as a benchmark.
I am all for extrapolating on known data but here you are making an error. HOI 4 was revealed early, under a previous release policy, and this backfired massively. The reason you know about HOI 4 is because the project was prematurely released and then delayed. I remember reading a post in June saying that under paradox's new policy it is unlikely we would have been informed about HOI 4 before PDXCon 2015. less speculatively Paradox is no longer revealing games before they pass to BETA. lo and behold stellaris has been revealed. we can, therefore, expect release in 6-8 months. This is of course subject to delays.
If I were to guess (complete speculation) bi-monthly dev diaries will start sometime in september.