My understanding is "the natural" in your example would be 0.4 if you are selling and 0.8 if you are buying
Daytrader, you are absolutely correct; I did not state that well. I tried to get one or the other of those two spreads filled but was succesful...
I tried really hard during the last 30 minutes of the market to fill put credit spreads (both 1150/1160 and 1160/1170) at midpoint of B/A spread...
Separate names with a comma.