TL;DR - 10.000 Research Points you receive as one-time bonus if you are eligible for Research Bureau.
If you have at least five Tier X ships researched, you will gain access to the Research Bureau, along with a one-time reward of 10,000 Research Points and the option to reset any of the researched branches of ships.
After resetting a branch, the Tier VI–X ships of that branch will have special Research Point marks which can be “scored” by gaining a victory in battle, similarly to bonus Stars of Victory. “Scoring” such marks will bring Research Points to players.
All branches excluding CV can bring you up to 10.000 points each after researching it again. CV branch can bring you up to 8.000 points because it takes ~20% less XP to research.