Tatsuya Hayami focused on improving automation reliability for headless deployments in the acemod/ACE3 repository by addressing a critical bug affecting group transfer ownership among Headless Clients. Using SQF scripting, Tatsuya updated the setGroupOwner function in fnc_transferGroups.sqf to reference the correct Headless Client identifier, _idHC3, ensuring that groups consistently transfer to the intended instance. This targeted fix reduced the risk of misrouted group ownership and minimized the need for operator intervention during automated scenarios. The work demonstrated careful code review, precise scripting, and effective use of Git-based change management, reflecting a focused and technically sound engineering contribution.