The first EX Raid Passes of 2018 for Pokemon Go have been sent out. As Pokemon Go Hub reported, the EX Raid Battles are back after an almost three week long hiatus.
According to a post by The Silph Road Reddit Administrator dronpes, over half of pass recipients are first time recipients. People who received their second EX Raid Pass make up a quarter of recipients and people who received three or more passes make up the remaining quarter.
Player level also seems to be a factor in whether or not you receive a Raid Pass. According to Pokemon Go Hub, trainers level 34 to 40 are more likely to receive Raid Passes.
Some players believe that they have found a way to guarantee an EX Raid to appear at certain gyms. According to comicbook.com, passes go out about once a week but only to players who previously completed a regular raid at the location where the EX Raid is to take place. Also, Raids mostly appear at sponsored gyms such as Sprint or Starbucks locations in the USA or locations that are coded as parks.
According to comicbook.com, One theory on how to get an EX Raid to appear is by using OpenStreetMap, the mapping system the game uses, and looking at how locations are divided into s2 cells or index reference points used by Google and other mapping systems in order to determine which gyms are eligible for an EX Raid to appear at. User anipm87 on The Silph Road subreddit found that Niantic distributes EX Raids at a rate of one per 12th level s2 cell and that a location will never have an EX Raid on two consecutive raid windows. So if a 12th level s2 cell only has two eligible gyms, you can focus on raiding the gym that didn’t last have an EX Raid to maximize the chances of getting an EX Raid Pass.