My big question right now is: is the plan to install new dichroics in PR2 and SR2 as well, or just in PR3 and SR3, where the green beams are extracted? I think the answer is no, we only want to install new dichroics in {P,S}R3.
Why not? The new dichroic mirrors have more transmission of 1064nm than G&H. Thus it will give us more POP beam and will help locking.