There is a new pull request by Chocimier against master on the void-packages repository

https://github.com/Chocimier/void-packages-org XBPS_USE_BUILD_MTIME
https://github.com/void-linux/void-packages/pull/28892

xbps-src: fix XBPS_USE_BUILD_MTIME option
Before, with XBPS_USE_BUILD_MTIME enabled, error `xbps-src's BUG: SOURCE_DATE_EPOCH is undefined` was reported.

A patch file from https://github.com/void-linux/void-packages/pull/28892.patch is attached