Changing source file

Hi
I have done a lot of work using a PSD file as a matte within a clip I am working on but I have now got a matte in mov format I wish to use instead as it is better. I would like to just change the source so all the automated transformation work I have done with the PSD is applied to the replacement mov. I was hoping I could just find somewhere to change the source something I can do quite easily in Fusion but I'm afraid I cannot find the same ability in Resolve 14 beta 5.
Can anyone help please
Many thanks Gary

Would Replace Edit do the trick?

Another thing you may want to look at is selecting the clip in the timeline, right clicking and disabling Conform Lock Enabled.

Then find the timeline in a bin, right click on the thumbnail and choose Reconform from Bins.

And finally right click again on the clip and reactivate Conform Lock Enabled.