While most of the Pokemon GO population is wrapped up in this weekend’s Rock-type event, dubbed Adventure Week, there is growing speculation that even more changes might be headed to the mobile game soon. And if true, some believe that fans may see a major overhaul for Gyms and potentially the introduction of the raid feature.

Obviously, most of the speculation surrounding Pokemon GO should be taken with a grain of salt, but there is some evidence to support it. Principally, fans are looking at the timing of the last major update, which hit around February 16th. That update added a whole new set of Pokemon into the game, drawn from the series’ gen 2 titles.

Assuming that the Gen 2 update is indicative of a timeline, then the assumption is that the next major update will release sometime this week. Again, there is no evidence from Niantic to support the release date, but quarterly improvements do make sense.

As for what players can expect from the major update, regardless of release date, most have pointed to the new gym raid feature as a likely focal point. When initially leaked, some assumed that raiding meant multiplayer battles against a single Pokemon opponent, perhaps a legendary Pokemon, but new data mine info suggests it might not be as involved.

While digging through some Pokemon GO patch files, data miners found new lines of code that point to an activity titled ‘Defeat Raid Pokemon’. The description is vague and could be interpreted several different ways. Some have taken it to mean that players will earn rewards for defending gyms, while others think it supports the multiplayer concept.

Whatever the case may be, Niantic has already said a major gym overhaul is in the works, so players can expect some changes regardless. Whether those changes are as big as fans’ hope is unclear, but thus far all of the developer’s updates to the mobile game have encouraged investment and attempted to bring lapsed players back. This latest update is expected to be no different.