diff --git a/lib/platform/github/index.js b/lib/platform/github/index.js
index 07d162a2b2629546f69107e2acd56343cd67bbbd..090730b87706781541dea3301ce0ccd38ca3427f 100644
--- a/lib/platform/github/index.js
+++ b/lib/platform/github/index.js
@@ -882,6 +882,7 @@ async function getOpenPrs() {
         json: false,
       };
       const res = JSON.parse((await get.post(url, options)).body);
+      const prNumbers = [];
       for (const pr of res.data.repository.pullRequests.nodes) {
         // https://developer.github.com/v4/object/pullrequest/
         pr.displayNumber = `Pull Request #${pr.number}`;
@@ -935,7 +936,10 @@ async function getOpenPrs() {
         delete pr.mergeStateStatus;
         delete pr.commits;
         openPrList[pr.number] = pr;
+        prNumbers.push(pr.number);
       }
+      prNumbers.sort();
+      logger.info({ prNumbers }, 'Retrieved open PR list with graphql');
     } catch (err) /* istanbul ignore next */ {
       logger.warn({ err }, 'getOpenPrs error');
     }