Renderdoc capture of the blurry frame is here - [Link Removed]
It should have symbols attached to it but let me know if not and I can reupload (Jon Cain)
It's coming from the motion blur pass but I didn't manage to narrow it further than that yet, I believe the issue comes from VelocityPrevScreenPosition being used in the Calculate3DVelocity function in VelocityCommon.ush, so the fast camera switching means that the position difference is significant.
Download the licensee repro here - [Link Removed]
Hit "Play" and open the console, set t.MaxFPS = 2
As the camera view switches, the first frame of each switch features a heavy motion blur, then the other frames smooth out.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-119606 in the post.