Vulture's green passive not firing when Jubilee changes colour of countdown

I noticed this in a versus match today.  My team was Nebula, Rocket+Groot, and Vulture, and on the enemy team, everyone was dead except for a second Vulture.

I fired off "One Fell Swoop" to make a green countdown and then went airborne.  On the enemy's turn, they fired a Jubilee "Light Show" team-up that changed my countdown purple.  When my Vulture landed, the countdown was not removed and no damage was dealt to the enemy team.