"Complete reworking" refers to making significant changes or improvements to something, which involves redoing or revamping it entirely. Full definition
The full changelog is as follows: Complete rework of the core... (crackberry.com)
But the holy grail of UX I hope to be a part of is a complete reworking of software development. (inc.com)
Wall Street Journal editor in chief Gerard Baker announced a series of sweeping changes to the Journal's newsroom, including a complete reworking of the paper's Page One structure. (nystateofpolitics.com)