I'll pick one of the most popular react boilerplates as an example here.

Assume, i've forked it (commits history till fork date remains intact). According to the text of MIT license, the only thing that I have to keep is the license itself. So, does it mean i can change whatever i want in this repo and remove/replace whatever references to the author (e.g. package.json author? Except one thing - reference to original author in the LICENSE file

And, also, I should replace this line on top of LICENSE file with this text:

Copyright for portions of project [Original project name] are held by [original author, year] as part of project [New project name]. All other copyright for project Foo are held by [new name, year].

Are these assumptions correct? Where can I find authoritative explanation of such details of MIT license?