I don't think there's a way to save those settings on the 705 when you do the update.
No the Audyssey settings will be lost doing the DSP update. There is a way to save your audyssey settings for other updates (firmware).
Thanks for gurkey over at avs.
1) TO STORE SETTINGS (must be done first, otherwise the recall will not have anything to recall):
Turn the unit on.
From the front panel- Push and hold "Setup", then Push "Enter".
The unit will display "Setup Store?", push "Enter" again and the unit will display "Setup Storing", then it will display "Complete" and thus the procedure is complete.
2) TO RECALL SETTINGS:
Turn the unit on.
From the front panel- Push and hold "Setup", then Push "Return".
The unit will display "Setup Recall?", push "Return" again and the unit will display "Setup Recalling", then it will display "Complete" and thus the procedure is complete.