Premiere/Resolve: different start TC on modified fps clips

This is actually a long-standing issue, I've been meaning to write about for years.

Often the editor in Premiere will change their footage framerates by re-interpreting it. Unfortunately Premiere also reinterprets the start TC when it does this. (As if the timecode were a derivative function of its fps.)

When I reinterpret the same clip in Resolve, it keeps the original start TC, (exactly as listed in the XMP sidecar, or TC track, but rounding the frame itself.)

I see the argument for both ways of doing it. But its a problem when neither program gives you that choice.

My manual solves to date have been either:

Manually modifying the start TC of every source media clip in Resolve to match its Premiere counterpart.
(Which at one point I'd built a macro to semi-automate.)

(or)

Zero'ing the TC in both Premiere and Resolve and using reel names.
(Which is easy to do in Premiere, though I no longer seem to be able to do it in Resolve. Which I used to have like 3 different ways of doing quickly. Not sure what I'm missing now.)

So I'm curious if anyone knows something that I don't on how to address this issue.

Thoughts?

I'm dealing with a great case study of it now- On a project with 4 different kinds of raw media, all 4 of which have native 60fps reinterpreted to 24fps. So I might as well document it as it goes.

Here are some more things of interest.

• It seems to be wrapper format specific. The mismatch is happening on the .MXF (with XMP sidecar) and .CRM, but the .BRAW and .MOV seem to handle it fine.
• Premiere is inconsistent with how it handles the conversion as well. If you output the same clip, with and without a simple speed change, you'll get different media start times.

And here is my current workflow:

• In premiere, prep your timeline, separating all speed warp clip to their own track.
• duplicate them to a new track, and remove speed attributes on just those duplicates.
• Export an XML containing everything except the original speed warp track.
• In Premiere, batch interpret source footage to 00:00 TC, for all problematic formats (i.e. MXF, CRM). Do this correctly, (and test first.) Or you will zero out the TC metadata on your clip.
• The formula for non-speed clips is: Zero'd TC, and target (modified) FPS source clips.
• Auto import XML into Resolve
• Repeat 00:00 process in Resolve for same clips, using a macro, or manually copy/pasting. (00:00 is faster than manually matching TC in premiere.)
• This should get you everything but the speed warped clips, correctly.
• Now duplicate that project, clearing any timelines and leaving the modified media.
• Change the FPS of the footage to their original rates, but leaving them Zero'd.
• Import an XML of just the speed clips. At least some of them should link.
• The formula for these speed clips is: Zero'd TC, and Original FPS source clips.
• Now create a new project, and import an XML of just the orig speed warped clips. Do not modify the TC of the clips it pulls in. At least some of the formats should correctly link up.
• The formula for these speed clips is: Orig TC, and Orig FPS source clips.
• Combine all the timelines of the projects (using dynamic project switching), and merge the clips in.
• You'll now have 3 duplicate media pool clips of the shots with and without speed warps. But you'll have what you need at least.