diff --git a/scripts/fetchdep.sh b/scripts/fetchdep.sh
index 02af402951..0990af70ce 100755
--- a/scripts/fetchdep.sh
+++ b/scripts/fetchdep.sh
@@ -24,19 +24,19 @@ clone() {
 # Try the PR author's branch in case it exists on the deps as well.
 # First we check if GITHUB_HEAD_REF is defined,
 # Then we check if BUILDKITE_BRANCH is defined,
-# if it isn't we can assume this is a Netlify build
-if [ -n ${GITHUB_HEAD_REF+x} ]; then
-	head=$GITHUB_HEAD_REF
-elif [ -n ${BUILDKITE_BRANCH+x} ]; then
+# if they aren't we can assume this is a Netlify build
+if [ -n "$GITHUB_HEAD_REF" ]; then
+    head=$GITHUB_HEAD_REF
+elif [ -n "$BUILDKITE_BRANCH" ]; then
 	head=$BUILDKITE_BRANCH
 else
-	# Netlify doesn't give us info about the fork so we have to get it from GitHub API
-	apiEndpoint="https://api.github.com/repos/matrix-org/matrix-react-sdk/pulls/"
-	apiEndpoint+=$REVIEW_ID
-	head=$(curl $apiEndpoint | jq -r '.head.label')
+    # Netlify doesn't give us info about the fork so we have to get it from GitHub API
+    apiEndpoint="https://api.github.com/repos/matrix-org/matrix-react-sdk/pulls/"
+    apiEndpoint+=$REVIEW_ID
+    head=$(curl $apiEndpoint | jq -r '.head.label')
 fi
 
-# If head is set, it will contain on BuilKite either:
+# If head is set, it will contain on Buildkite either:
 #   * "branch" when the author's branch and target branch are in the same repo
 #   * "fork:branch" when the author's branch is in their fork or if this is a Netlify build
 # We can split on `:` into an array to check.
@@ -44,19 +44,26 @@ fi
 # to determine whether the branch is from a fork or not
 BRANCH_ARRAY=(${head//:/ })
 if [[ "${#BRANCH_ARRAY[@]}" == "1" ]]; then
-    if [[ "$GITHUB_REPOSITORY" = "$deforg/$defrepo" ]]; then
-        clone $deforg $defrepo $head
+
+    if [ -n "$GITHUB_HEAD_REF" ]; then
+        if [[ "$GITHUB_REPOSITORY" == "$deforg"* ]]; then
+            clone $deforg $defrepo $GITHUB_HEAD_REF
+        else
+            REPO_ARRAY=(${GITHUB_REPOSITORY//\// })
+            clone $REPO_ARRAY[0] $defrepo $GITHUB_HEAD_REF
+        fi
     else
-        clone $GITHUB_ACTOR $defrepo $head
+        clone $deforg $defrepo $BUILDKITE_BRANCH
     fi
+
 elif [[ "${#BRANCH_ARRAY[@]}" == "2" ]]; then
     clone ${BRANCH_ARRAY[0]} $defrepo ${BRANCH_ARRAY[1]}
 fi
 
 # Try the target branch of the push or PR.
-if [ -n ${GITHUB_BASE_REF+x} ]; then
+if [ -n $GITHUB_BASE_REF ]; then
     clone $deforg $defrepo $GITHUB_BASE_REF
-elif [ -n ${BUILDKITE_PULL_REQUEST_BASE_BRANCH+x} ]; then
+elif [ -n $BUILDKITE_PULL_REQUEST_BASE_BRANCH ]; then
     clone $deforg $defrepo $BUILDKITE_PULL_REQUEST_BASE_BRANCH
 fi