# Interpretation of permanganate-stained TLC spots

When I stain TLC spots with $$\ce{KMnO4}$$, I found that some spots appear differently as time goes by. Here is the example:

The leftmost one is the plate right after staining, and the others are listed sequentially with time.

Question 1: As time goes by, some white stains appeared and widened. Does this mean some materials exist in that area, or is this just result of diffusion? Are the white stains due to original yellow spots, or indicate the existence of different materials?

Question 2: Some white stains (numbered as 1, 2, 3) appeared in the same manner, but disappeared. Then should I consider the existence of this white stain? And should I record staining with time-scale whenever I stain the TLC with $$\ce{KMnO4}$$?