rbartell- I'm sorry you had this happen, but I'm not sure from reading the ARCA erroneous trade policy that it says what you describe, I.e. That any new 52 week high/low can be busted in the pre/after-hours. It does say that a new high/low is a factor to consider for outliers that don't otherwise exceed the thresholds (in 7.10(d)(1)(B)), and in 7.10(c)(3) all they say that they have discretion to consider various potentially relevant factors.
It seems to me that the threshold for a $0-25 priced 2x ETP would be 20% away from the reference price, or 10% in the case of $25-50 priced ETP. The reference price would typically be the last trade, or perhaps the most recent open/close under more extreme circumstances.
