From: iTunes Store <firstname.lastname@example.org>
We have discovered one or more issues with your recent delivery for "...". Your delivery was successful, but you may wish to correct the following issues in your next delivery:
Non-PIE Binary - The executable '....app' is not a Position Independent Executable. Please ensure that your build settings are configured to create PIE executables.
If you would like to update your binary for this app, you can reject this binary from the Binary Details page in iTunes Connect. Note that rejecting your binary will remove your app from the review queue and the review process will start over from the beginning when you resubmit your binary.
The App Store team