Fresco timelapse - strange black frame and zooming bug!?

Hello community! I've been using Fresco for a few years now and make extensive use of the timelapse export feature. Recently, I've encountered a strange glitch/bug in my exported videos where the video starts slightly zoomed out with a black frame around the drawing canvas and then proceeds to jump-zoom into the canvas, the black border getting thinner each time until it disappears and the video plays normally. At first I thought it was a bug caused by using the layer mask in my original drawing, but the phenomenon is also occurring in drawings without masks. I've been test exporting new drawings every few minutes, to see if it is a  particular tool that introduces the bug, but I have not found a consistent culprit. Note: many drawings will export normally for a little while and then at a certain point, the black border/zoom-out appears at the BEGINNING of the video, so it is also not chronological. The problem was occurring with my canvas size set to 4096 x 2304 (to max out the horizontal dimension and keeping the HD dimensions). I have downsized my canvas dimensions slightly from that size to 3840 x 2160 (2x Full HD dimensions) and have had no problems in my current drawing so far (fingers crossed). I've attached a test video for reference.

Tech details:

- Fresco 3.4.2

- iPad Pro (12.9 inch) 5th Gen 256 GB storage (142 GB available)

- Timelapse settings: Quality - High, Resolution - High (up to 4096 x 4096)

- Drawing canvas dimensions 4096 x 2304