message: Check for errors if the timed signature expires
diff: @@ -60,6 +60,10 @@ export async function waitForUnpack(ctx, url) {
  try {
  res = await ctx.http.fetch(url, {}, { retries: 0, noLogErrorBody: true });
  } catch (e) {
  + const { response = {} } = e;
  + if (response.status === 403) {
  + bail(new Error('Provided signature expired.'));
  + }
  throw new Error('Sentinel file not present.');
  }
  