Niantic has published the Mission Day application form for Q4 2023!
Along with it, the Q3 2023 form has been re-posted and both of them have new deadlines:
Q3 2023 form: submit by May 15th
Q4 2023 form: submit by August 15th
If you are interested in hosting a Mission Day in your city, make sure to read the Ingress Mission Day Guidelines first as they contain all the requirements and information to organize a proper event!
Source: https://ingress.com/news/2023-mission-day/?hl=en
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