How do I deliver a 5.1 + LtRt ProRes 422 using premiere 2020?

I was just guided through this process and it was relatively simple:

1) Create a new Sequence (select whatever codec)

2) Click on Audio settings and set to 5.1

3) Copy old footage from SEQ and post in new sequence.

4) Delete any unused tracks

5) Now in audio export 5.1 options should be available.

I'd be interested on hearing how you mixed the LtRt as it's not simply a left and right pan, that's called LoRo. 

LtRt is 5.1 compressed into two channels which rather cleverly is then split back into 5 channels (misses the LFE) by dephazing the audio. So you have to put some of the tracks at 90 degree phasing to the others. Otherwise when a player decodes LtRt and it's not encoded properly it will sound very wierd. 

You'll need to create a Sequence with the Audio Tracks configured for 5.1 so that you can export with the Audio set to 5.1.

I've attached some screenshots.  

For what it's worth, I usually have a sound mixer create stems of each component of the 5.1 mix properly named and then import those back into Premiere Pro.  From there, the placement in the corresponding tracks and mix assignment is easy.

and of course the issue is that I've had to do this maybe 3 or 4 times in a very long career.  And each time I tear my hair out trying to remember how to do it.  Needless to say, each time there's less and less hair to pull out.  And of course the first time was probably on avid, the 2nd and 3rd on FCP7 and now Premiere.  

figured it out and it ain't intuitive.  You've got to create a new sequence with 8 tracks of audio.  Here's where it gets kind of stupid.  Premiere only allows track assignments as pairs.   So you've got to assign channels 1 and 2 to to 1 and 2 (a single choice), and 3 and 4 to "3 and 4" and then pan 1 left, and pan 2 right, pan 3 left and pan 4 right, etc.  

and then in the export settings set the output to 8 mono channels.  at least that's what I think I did.  I know I brought the exported clip back in to premiere and it seemed to be working right.  since I only have my setup to monitor 2 channels, the other 6 channels weren't audible but I could see the audio levels.  Hopefully this well help you figure it out for yourself.  Now if I could only get another feature job...  Post back with any questions.

I'll see if I can figure it out but it may take a day or 2 til I get to it.  Hopefully someone else here will pipe up.  Have you tried googling "exporting a quicktime with 8 tracks in Premiere Pro?"

You'll need to create a sequence in premiere with 8 mono tracks and put the tracks on it as per your specs.    Once that's done... I can't really remember, but start by telling us your delivery specs.  When I've had to do this for distribution to netflix, itunes, etc I had to deliver a prores 422(HQ) file if I remember correctly.  Once you tell us your delivery format, someone here can help you with the export workflow.  I might even be able to remember how to do it.