The overground rebranding cost is £6 million.
https://www.london.gov.uk/who-we-ar...e-log/foi-overground-line-rebranding-mar-2024
This represents less than 1% of the £700 million value of the cut to TfL's grant.
https://www.london.gov.uk/tfl/tfl-funding-settlement-another-short-term-sticking-plaster
Or, just over 1% of the £500 million cost of the Central Line Improvement Programme.
Therefore, I don't think refreshing the station signage on the overground stations (some of which has probably been in situ for the entire 17 years of Overground) is a direct cause of situations such as delays to the CLIP, or a cutback on non-essential maintenance like graffiti repair.
The fact is the massive cuts to TfL's budgets, and the more restrictive access to investment funding from the Treasury (for e.g. New fleets and heavy refurbishments such as the CLIP) are the major causes.
Also, I'm sure that if TfL did repair graffiti on a unit that was about to be stripped out and refurbed anyway, someone would come along and decry the waste of money