multiple images can't be handled by 'Image Blend' nodes

[SPierceMyers]

I really like these nodes. Thank you for them.

The Image Blend nodes work well for blending single images. But I'm trying to use the Image Blend by Mask node to process a sequence of images. I have some camera footage (image_a), diffusion images based on that footage (image_b), and mask images derived from yolo (mask). But I get the error:

Error occurred when executing Image Blend by Mask:
Cannot handle this data type: (1, 1, 540, 3), |u1

All of the images are the exact same frame rate, frame count, aspect ratio, pixel count, etc. etc.

Perhaps this is not a bug, but just not yet a feature. Any ideas on how to achieve this?

Best

ps '540' is the width of the images
and this node also works perfectly for processing a single image (ie, 1 frame of the video at a time)