Build 29981 was released to the PTR on April 8, 2019 and the next day, April 9, 2019 to Live. It was replaced by Patch 8.1.5hotfix9 on May 31, 2019, but restored on June 1, 2019 for some reason. The build after the re-release of this build was Patch 8.1.5hotfix10.
Patch 8.1.5 hotfix 8
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