Understand, I read that and pulled part of your reply into the other thread.
If I understand the rules that you are referring to Paratroopers only receive their bonus support when they are only attacking alone, and only for 1 round of combat. That is why I don't think @Azimuth idea for using "whenHitPointsDamagedChangesInto" will work, because other attacking units need to be considered.
Rule quoted in question:
When Paratrooper units attack by air the attack
factor is “3” in the first round of combat.
From the second round of combat the attack
factor is “1”.
If Paratroopers attack by air and are supported by
units other than Paratroopers, the Paratroopers
attack at “1”.
So, when a Paratrooper attack only with other Paratroopers, they attack at 3, when supported by other units they attack at 1. This would require a self-support, plus a cancelation support from other units. Both would need max round limited to 1:
<attachment name="supportAttachmentParatrooperSelf" attachTo="Paratrooper" javaClass="UnitSupportAttachment" type="unitType"> <option name="unitType" value="Paratrooper"/> <option name="faction" value="allied"/> <option name="side" value="offense"/> <option name="dice" value="strength"/> <option name="bonus" value="2"/> <option name="number" value="1"/> <!-- New option to check for rounds --> <option name="maxRounds" value="1"/> <option name="bonusType" value="ParatrooperSelfSupport"/> <option name="impArtTech" value="false"/> </attachment>Would this help?
Cheers...