P: Cannot merge panorama after updating to 10.14.6

I can tell you that batch processing a few files a couple of them took way longer than others. I don't know the reason behind it. The files are roughly the same size and number of photos in a pano are the same, but I have had some panos take much longer than others. I figure it will take them another update to even everything out, at least it works again. 

Been really struggling to stitch pano's from my holiday after not having done it for a few months, they were taking ages and many looked like they had hung. This morning I let a 25 RAW image HDR pano build run and it took over 4 hours but it did eventually complete. Stumbled across this thread, updated my OS and built the same pano in under 2 minutes. Things look back to how they used to be. Thanks to everyone who helped sort it.

57 uncompressed raw file (85MB each) hdr pano just completed. Used 107GBof scratch space during merge (1.1GB output file) which is in line with expectations. Great to have my system back working again.

Tbh in my case I think it’s now back to normal.

Am I the only one who feels that (although working) it's still slower than before?

Wow, finally, it works perfectly fine after the above suggested update of Mac OS, thanks for your kindly help and wish more people who have the same issues can see this post! Thank you so much for your efforts on this. 

Problem Solved. Thanks a lot! 

Jeffrey, thank you to you and the teams on both sides that worked on this issue.

I just did  11 shot and 12 shot panos that I quit the merges before the Apple update as they seemed to be stuck and they merged after the update.   Time will tell.

BAM! Just created my first 21-stitch Pano from Lightroom in weeks. Thank you! Update did the trick.