The deadline is October 15th for the following:

The Wikimania Steering Committee and Wikimedia Foundation are seeking expressions of interest from interested parties for hosting Wikimani a 2020.

Please see the following for more information:

https://meta.wikimedia.org/wiki/Wikimania_2020

If you are interested in discussing the possibilities and working with the WMF Events Manager in preparing a proposal to host and organize Wikimania 20 20 , please contact eyoung at wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikimania-l by October 15th. Also, if you know of an individual or group that we should approach about hosting, we encourage nominations as well. The Steering Committee and WMF expect to make a decision by early 2019.

Thanks, Ellie