Indigo, DD previously had an abbreviated test for school's program. These brief results gave DYS-level scores, but no extended norms are available for this brief test (and it would appear DD hit a couple of ceilings). I'm not the professional, but from what I understand, when a full test is later performed, all subtests can be administered (so "finishing" it is actually a bit of a misnomer, but is just how I'd been thinking about it), substitution of subtests is considered to avoid any "practice effects," to achieve a full WISC. There is actually a bulletin out that describes the procedure.