Does the advanced command and Staff Course come before the HCSC? Or are they for completely different routes? Maybe my question should have been about a degree for ACSC.
When I was involved with it, a decade or so ago, ACSC was for SO2s tapped for promotion, and was about forty weeks long ending in a two-week wargame. It struck me as being very heavy on staffwork and process, to the point that players were refusing to listen to the morning updates on the situation because they were busy putting slides together for that afternoon's Joint Effects Meeting (neglecting the issue that the update was, that RED had just managed a surprise seizure of the key objective for the campaign, completely transforming the joint effects that were now required... some firm correction applied by EXCON there).
HCSC was for OF5s destined for greatness (ran into both Jerry Kyd and Tony Radakin there) - thirteen weeks and much more focussed on "levers of power" issues than "how to be part of a big HQ", and therefore rather more interesting to support. There, their final war game was much more focussed on operational and strategic issues, such as one case where Blue actually managed to effectively prevent the conflict from breaking out at all by a very smart combination of diplomacy, economic pressure and military bluff (complaints that "it's not the Theatre
Peace Game!" and a reset of "very well done, but we all want a proper scrap, so RED
do invade and the fight's on..."
I did enjoy supporting both, and learned a fair bit by doing so. While I did get some opportunity to do ACSC (as a civilian) it seemed somewhat limited in relevance for the time involved, so I didn't pursue it: I was (perhaps hubristically) angling to be the first Dstl analyst to do HCSC (on the young side at the time but building my case - OGDs did send occasional civilians on it) before events overtook.
And since my last direct contact with it was in 2013 or so it's doubtless all changed since then anyway...