upstream has license which is an edited GPL
I was going to package CDDE  but noticed that upstream ships it with a
license file which is GPL v.2 without the preamble and the appendix
so it starts from
GNU GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
end ends with
END OF TERMS AND CONDITIONS
Within all the source files he mentions the standard GPL v.2 notices.
I have e-mailed the upstream explaining that changing GPL and removing its
copyright is not allowed, but I am interested in the following. If he does
not reply can I repackage or even fork his source which is under such a
license? Technically, it has all the terms of GPL, however I am worrying if
what the upstream has done makes his resulting license legally void.