What I have done
There's PHP tool which uses Bitbucket API to deploy code on environments without Git etc. It's licensed under GPLv2 or any later.
Bitbucket API is shifting from v1 to v2, and it's impossible to achieve same thing with API v2 just by design - it doesn't allow to get code of individual files.
I have created my own workaround version, added features, cleared up spaghetti & WET code etc, So ending up heavily rewriting original code - only 40 lines of two helper functions have stayed intact and even then those two functions maybe was found online as examples.
The thing is I want to release it as my project (complying with original licence)
Would it be fair if I rewrite
readme.mdstating it's my own, but referring that was inspired by what original work.
Should I keep doing it on forked project or should I take down fork and release it new clean repository?
Is it o.k. if I continue original versioning with new major version, or should I start everything from zero?