Personally I never change anything. Sure, it will give you a little more float but you can leave your bindings in the optimal spot to utilize the flex of the board most efficiently and use good riding technique to accomplish the same thing. It's all about front foot retraction way more than leaning back.
I remember my Arbor wanting to DIVE under unless i leaned back heavily , on deep days. on the other hand the same board all set back ( 6 cm more or less) floating much better and letting me enjoy longer days before leg burn. Sure the going was surfier, but in pow that's actually good. IMO
2015/16 -17- Kirkwood days
Arbor A-Frame 158 2009-10
Jeremy Jones Hovercraft 156, 2011/12
Subaru WRX 06 - 181K