Well, I haven't heard from anyone in the group about this, but based upon my experiments, the answer appears to be "yes".
The program does indeed treat the paragraph in which the table is anchored and the table as one "span". The next page returns to default left/right (as I did not specify another choice).
However, in one experiment I included the paratag "Body Next" in the reference page table, specifying explicitly that this tag should trigger a return to the default master pages. In this instance, I entered a Body Next paragraph immediately following my multipage test table, on the same page where that table ended, and the last page of the table was formatted using the default master pages.
An implication is that, to return cleanly to a new page at the end of a multipage landscape table, one might choose to follow the table with a paragraph using a top-of-page paratag other than that used to anchor the table in the first place, having entered that top-of-page tag in the UnstructMasterPageMaps reference table.
Hope this seems clear. From my perspective, this function works exactly as I anticipated.
Best to all,
Elchanan