Thank you for the guidance. We'd like to send you our triangle-only Xcode reproducer for an integration and timing review. We submitted a code-level support request on Oct 28, but haven't received an acknowledgement email or case number. The forums uploader rejects ZIP files. Could you provide an Apple support email address for sending the project, or a preferred private upload channel? Our main question is whether the ~11 ms FI cost at 2622 x 1206 can be reduced.