hi Fae,
I think User:AroundTheGlobe's suggestion would be great to get you people to help with the hosting/coaching people who'd like to edit in the South Asian languages in addition to the editathon.
For people who cannot directly make it to London, I believe there is provision for e-volunteering as well. If you could elaborate on that, it'd be great.
warm regards, Pradeep Mohandas