Professionally ignore people with style.

Your email has located me at an impressively inconvenient moment. I am at an event where every hallway conversation became a calendar liability. Cross-functional anxiety should be routed through someone with more availability. I will get back to this once I return and the panic cools down. For urgent issues, contact the team lead or whichever vice president loves escalation the most. Thank you for your measured response to my unavailability.