I posted on CloudyNights a 4-stage sliding-scale model for PN-ISM interaction that was proposed in a 2007 paper by Wareing, Zijlstra ,and O’Brien.

• stage WZO1: the PN expands freely within the bubble of the undisturbed slow AGB wind material and is unaffected by the AGB wind-ISM interaction.
• stage WZO2: the PN interacts with the bow shock formed during the AGB wind-ISM interaction process, and the density and the emission in the upstream side increases accordingly;
• stage WZO3: the geometric center of the PN is moving downstream away from the central star
• stage WZO4: the PN is completely disrupted and the central star is outside the PN.

In a 2012 paper by Ali et al "Interacting planetary nebulae", HDW 1 = EGB 1 is classified as stage WZO3, so approaching the HASH classification. The link here is for the VIZIER page on HDW 1 from their survey.