You might want to look through earlier pages. If I remember correctly, @Anmdt had said a few times that Hisar-D (based on Hisar RF) and Siper's first block (based on Hisar-RF + booster) will be quadpacked as this is a requirement by the Navy. Ibrahim Sunnetci also confirmed the quadpacked Siper a few months ago. It seems quadpacking will not finish in time for the first frigate, though.