Petition to rezone Woolwich on the tube map

A petition has been set up calling on the Mayor of London and TfL to move Woolwich from Zone 4 to Zone 3 on the tube map travel zones. As the petition states, Woolwich DLR is the only DLR station in Zone 4, while it notes that most of the zone 3 stations north of the river are of equal distance from Central London.
The financial impact on passengers would be significant as a monthly zones 1-4 travelcard currently costs £204, but this could fall to just £167 if Woolwich was moved into