Via Dutch news website Het Parool: https://www.parool.nl/amsterdam/oud-telegraafgebouw-wordt-uitvalsbasis-guerrilla-games~a4601684
The new building:
Currently re-construction is going on at the new building. Guerrilla Games' 250 employees and representatives from Sony visited the new building today (July 18th 2018). Currently Guerrilla Games employs about 250 people, with the new building they want to grow to at least 400 employees. Hermen Hulst also talks about some other recent developments at the studio, such as the fact that just in the last month Guerrilla hired 9 new developers. Guerrilla Games will aim to release 1 new game every 2-3 years, in that timeframe they want to release both new IPs and new games based on existing franchises.