If we have a DB & DC plan that is aggregated for 410(b)/401(a)(4) and general tested together for (a)(4) discrimination, do the 401(k) deferrals get reflected in the DB's MVAR at all ? I believe the deferrals are included in the NAR for ABT (unless there some disaggregation option available ??) Thanks for any input.

The deferrals go into the ABT but not the Nondiscriminatory Classification Test, which is kind of what your second sentence says.

P.S. But the ABT is often not needed anyway, if each rate group in the NCT passes the 70% ratio/percentage test. In that case, the deferrals are not in the test at all.