Britney says "Rejected due to piuparts regression"but piuparts.debian.org says "succesfully tested".

[Peter Michael Green]

https://tracker.debian.org/pkg/rust-gtk says "Rejected due to piuparts 
regression - https://piuparts.debian.org/sid/source/r/rust-gtk.html"; but 
when I follow that link it says "successfully-tested 0.14.3-1". This has 
been the case for several days so it doesn't appear to be a transient 
issue of different webpages updating at different times.

Can anyone provide advice on how I should find the source of this problem?