Smoke replay not updating

The short version of my question is this: How do I get the realtime smoke preview up update to reflect changes to the scene?

The long version is:

I’m playing with smoke sim in 2.90. I just used the “quick smoke” option, so I can’t mess up any settings. With cache type set to “replay”, the smoke domain does a fine job of simulating the smoke movement, so I can see where it will go when I do a full bake.
However, once I’ve run in the animation once, it doesn’t update with changes to the scene. In other words:

  • Create quick smoke
  • play animation so the realtime preview sim can do its work
  • move smoke inflow object
  • smoke is unchanged, emitting from where the inflow object was when I first ran it

So basically as far as I can tell, it’s not clearing its realtime preview cache.
I can get around this by changing the cache type from “replay” to “all”, and then switching back again… but surely I’m missing something, because that’s clearly just a workaround.