The ALS reference cavity was in an unstable mode and the PLL could not get locked.
I re-locked the refcav with these settings:

Coarse 384
Fine 206
Common 300
Fast 638
Offset 194

The fiber output has dropped from ~300 uW to 80 uW since Bram installed a Faraday at the output of the reference cavity. As a consequence the beat note amplitude is about -25 dBm (-35 dBm at the monitor spigot of the phase/freq discriminator board). I had to increase the laser power otherwise the amplitude would have been even smaller.

The PLL is now locked again, with the laser at the end station set to 42.27 degrees.

Locking the PLL was tricky. One of the switches in the CMB_A MEDM screen was actually stuck in an open state, although it appeared to be closed on the screen. the switch was malfunction and it had a state value of 65536 instead of 1 or 0. I forced it to be 1 by EZCAWRITE.

Also there CMB_A board Input1 gain is now limited to -16 or less, vs -6 as it used to be, because the PLL becomes unstable at -15 and up. This is strange since the loop gain phase is flat up to 80 kHz and the phase margin is large (~60 degrees up to 80 kHz; the UGF is 10 kHz). I suspect something might be wrong with the slow control interface of CMB_A.