I was trying to figure out how to run the MC alignment offset calibration this afternoon, but ran into some difficulties with new features of the guardian / IMC ASC system. I wasn't able to turn off the ASC loops without the IMC alignment drifting. This wasn't an issue previously, though that was back in February.

Unfortunately, after tinkering with some of the ASC switches etc., the IMC alignment seems to have got into a bad state where it locks, and then drifts in alignment, and then unlocks after about a minute. I put the guardian mode back to exec, and requested locked, but each time the IMC locked the alignment drifted until lock was lost.

To avoid a possible runaway drift overnight, I've put the guardian requesting down.