Managerial oversight of Dutch academics: how much permission do I need to ask? In two weeks time I am leaving the UK for the Netherlands. I am new to Dutch academia and while, for the most part, it seems to be much like UK academia, I am curious about, for lack of a better term, the level of managerial oversight over Dutch academics for day-to-day comings and goings and decisions about scholarly activities. 

In the UK, it was expected that I work roughly 9ish to 5ish, 5 days a week, but more or less was up to me. Working from home did not need to be reported to anyone and if one was where one was meant to be when one was needed, it didn't really matter what happened at other times. I did not need to seek permission to attend conferences or workshops or to say yes to academic activities or opportunities. 

What is managerial oversight like in the Netherlands? I don't want to either anger people by not asking when I should, or annoy people by asking often when I don't need to.

I know that to some extent this will be institution specific, but I believe that those here with Dutch experience would be able to speak to what the general expectation of reporting to and permission from line managers is compared to that, generally, in the UK.
I think (in both the UK and in NL) this is very much down to the personality and management style of whoever is responsible for supervising you and signing off on your expenses. On the whole I would say that attitudes in NL are similar to those in the UK, and provided you don't give anyone cause for concern you'll be left to your own devices. 

That said, attitudes are set in a broader cultural context, and in NL conformity and a visible work ethic are valued.  In particular, I would suggest that people in Dutch academia are in general much more rigid about their working hours (8:30-5) than in the UK, with a better-defined home/work separation. "Working from home" as a matter of routine is not really a thing in NL. Continuing to follow the UK pattern will probably be fine with your bosses, but it may be frowned upon by your colleagues.