Strange warning during jessie to stretch upgrade

[Tony van der Hoff <lists@vanderhoff.org>]

Hi,

W: APT had planned for dpkg to do more than it reported back  (0 vs 4)

Affected packages: pypy:armhf

Google reveals some bug reports (850327 for Debian), but no resolution.

Can anyone tell me what it means, and can it be safely ignored?