diff --git a/.ci/dev/regression/Jenkinsfile b/.ci/dev/regression/Jenkinsfile
index 388d64360c..b805ff0fd8 100644
--- a/.ci/dev/regression/Jenkinsfile
+++ b/.ci/dev/regression/Jenkinsfile
@@ -248,7 +248,7 @@ pipeline {
                     // Comparing the dates of the previous and current builds achieves this,
                     // i.e. we will only send an email for the first build on a given day.
                     def prevBuildDate = new Date(
-                            currentBuild?.previousBuild.timeInMillis ?: 0).clearTime()
+                            currentBuild.previousBuild?.timeInMillis ?: 0).clearTime()
                     def currentBuildDate = new Date(
                             currentBuild.timeInMillis).clearTime()