DP48 presets and returns

Recently installed 6 DP48 with a Wing console for our church. Question is concerning storage of presets on the DP48. When you store a preset, does it store both the A and B mixes on the one storage slot? Is there a way to store A and B mixes independently? we are using the A mix for our stationary musicians and the B mix fed back to the Wing and routed out to wireless IEMs for the vocalists. The musicians are usually the same but the vocalists change from week to week and it would be great if they could save their mixes separately from the musicians.

In regards to the 8 channels returned on the AES50. Does anyone know if anything is on 7 and 8? Channels 1 and 2 are the A mix. 3 and 4 are the B mix. 5 and 6 appear to be the ambient mics. Thanks for the help.