May I ask: In your example, a 15 delta short is ~ 1 SD OTM and 30 delta is ~ 0.6 to 0.7 SD. What is your reason for choosing 30 delta to exit/adjust or it is not your real exit delta? Thanks.
While we're on the subject of stops...here's what else can happen. IB is pretty good in most areas...amazing in many areas, but like any broker - they have their days. At 5:55pm, all my GTC futures options (SP) orders get cancelled. They just turn red. This would NEVER happen on a normal Sunday open. In fact I'm generally not even looking at it Sunday night. The ES opens down 37 and it's a lil choppy because Greece can't pull it together. I try resubmitting my orders thru the combo tool that works every hour of every day and I get nothing but error messages - "contract not supported". I can enter some contracts manually (old school) but only one at a time and no combo's or spreads. The market is stable, albeit down a good bit...and two hours later I still can't get the interface to function properly. So....if I had stops, they would have been cancelled and I may not be able to get into or out of anything that I have. Nothing is guaranteed...even with a basic 2% down move after hours. This is a risk you always have to consider when you are holding anything overnight.
I have only been trading options in earnest past six months after back testing for 18 months. For what I do which are credit spreads, I trade directional and average down on losing trades, but at no time after adding onto losers the losses exceed 2% of account, But when I start adding on, am also doing opposite side at same time, so if I been putting on Put Credit spreads I will do Call credit spreads till market starts turning around then lifting the short calls. So no, I don't use stops at all since credit spreads have limited losses. Method I have designed will initially lose on 50% of original signals and using several months term options so between time decay and reversion to the mean is what I target to gain.
I chose 15 and 30 deltas out of thin air just for an example. There's no right or wrong delta levels. Whatever works in your comfort zone. I usually adjust/close in steps at different delta levels - ie close half at delta A, close the other half at delta B.