So im compiling all the details even rumors regarding lol mobile or League of Legends Wild Rift release date. So here we go!
Fire news was by Riot Games that plans to bring a new that League of Legends Wild Rift Riot to mobile devices and consoles earlier in 2019, however this didn't happen or maybe it dead at least as a beta release
Then here are this floating rumors
According to the Beta Information
January 22 2020 release?
Now an email sent to EVERYONE with a Riot account to make sure your account is updated before the 22nd, not sure if this is related to LoL Mobile
May 31, 2020 launch date?
From lol wild rift reddit
Update: March 18 2020
We still need more time before we move into our next round of testing
We're still heads down at work on Wild Rift so don't expect too many updates anytime soon. We will be back later this year with another update on our progress
Brian Feeney confirms that there is no version of Wild Rift is available to download in the internet right now
Riot Games designer, Brian Feeney
Fire news was by Riot Games that plans to bring a new that League of Legends Wild Rift Riot to mobile devices and consoles earlier in 2019, however this didn't happen or maybe it dead at least as a beta release
Then here are this floating rumors
Due to Google play store policy, there a high chance of soft launch in 14.01.2020 . Not to mention that, 2 more game of Riot will be release in near future. But sadly we don't get any beta news yet. That mean beta is coming in 2 or 3 days? Riot didn't announce any news officially. So that all just prediction.
According to the Beta Information
In North America the game is expected to start in the second quarter of 2020, in SEA (Southeast Asia) - in the third quarter of 2020, other countries - the last quarter of 2020.
January 22 2020 release?
Now an email sent to EVERYONE with a Riot account to make sure your account is updated before the 22nd, not sure if this is related to LoL Mobile

May 31, 2020 launch date?
Designer of Teamfight Tactics, Stephen "Mortdog" Mortimer, held a Christmas stream on his personal Twitch channel where he dressed up as "Santa Mort" to showoff some gameplay of TfT, did a Q&A, and giveaway for the gamers. During the streaming, he mentioned that players could expect the game to go live before May 31, 2020
From lol wild rift reddit

Update: March 18 2020
We still need more time before we move into our next round of testing
We're still heads down at work on Wild Rift so don't expect too many updates anytime soon. We will be back later this year with another update on our progress
Brian Feeney confirms that there is no version of Wild Rift is available to download in the internet right now
Riot Games designer, Brian Feeney
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