Question How to Properly seat Mixed Memory (Size) on a Dual Channel System?

Jan 23, 2021
Given a motherboard that supports dual channel memory and (4) DDR4 DIMMs of the same Manufacturer, Timing Spec, and Operating Frequency, but different sizes 2X 16GB and 2X 32GB = 96GB.
How do you properly seat the memory to Maximize the Dual Channel Benefit?
The motherboard has 4 memory Slots, 2 for Channel A and 2 for Channel B. From the install instruction, if I had two sticks of different sizes a 16GB and a 32GB the first 16GB of the 32GB stick would be mapped for Dual Channel use and the remaining 16GB would be mapped as a single Channel.
But there is no Guidance in my scenario. If I placed the 32GB sticks in opposite channels along with the 16GB in opposite channels, would that give the full benefit for Dual Channel Memory on the entire 96GB?
Currently we have 64GB in Channel A and 32GB in Channel B, I am afraid we are needlessly mapping 32GB for single channel use. Or maybe it doesn't matter?
Motherboard is: ROG STRIX B550-F GAMING
Thanks for any guidance.