Why can't INDIRECT() take a dynamic array reference just after opening a file?

I have a formula containing INDIRECT() pointing to some range -- call it B4:F8.

If I specify the range explicitly, like this:

=INDIRECT("B4:F8")

then it works fine.

However, if the range in question is actually a dynamic array, of unknown size but anchored at B4, and I use the # spill operator to specify it, like this:

=INDIRECT("B4#")

then it still works fine, except just after opening the file. On first opening the file, the formula returns #REF. However, to make it work all I have to do is force a recalc, by hitting F9 or even just putting my cursor in an empty cell and hitting Return.

Can anyone explain what's going on?

Here's a screenshot of an example, shown just after opening and before hitting F9.The formulae above each table show the contents of B4, H4, and N4 respectively.