I wrote an RAM simulation script ... it calculates the LSC signal offset and the operation point offset depending on the RAM modulation index.
Configuration : RAM is added on optC1, by the additional Mach-Zehnder ifo before the PRM.
Both are for PRCL sweep result. Note that REFL33I is always almost zero. Next step: Check the LSC matrix with matrix at the offset operation point.
On the right figure, you see the non-zero operation points even when RAM mod index = 0. Apparently they come from non-zero loss of the model. (Each mirror of 50ppm loss was assumed).