5.7k edit in Premiere Pro

Hello,

Wondering if anyone has tried importing, editing and exporting 5.7k stitched video from Premiere Pro and retained 5.7k? Each time I try, Premiere exports at 4K. The video still looks good, but would like full resolution.

As another path, I've attempted to edit the individual 2880x2880 resolution files created when running at 5.7 raw. Premiere will export the correct resolution on these files, but when I attempt to replace these files on the SD card to stitch in the Virb app, it will not allow me to stitch the two files.

I'm using Premiere CC 2017.