If the new item is added to the list box by reloading the app, I believe the "1688 of 1732" is correct.
You began with "43 of 1731", then reverted by selecting the excluded option. This will select the remaining 1688 items anad clear the existing 43, which is in accordance with the logic.
Now, when you add a new item to the list box (by reloading the app), QV maintains the selection of all the possible items from 1688 selections prior to reload. This changes the selection state to "1688 of 1732".
What you are expecting QV to do is select the new value that is added after reload, which is not possible.