Again, according to Innes Ferguson, TfL's medium-term aspiration is for the former to be expanded to cover other National Rail services in London and the South-East, either by direct TfL operation through a concession-holder (as with the ex-Silverlink routes) or by a TOC agreeing to operate under the London Overground "brand".
Innes Ferguson states that TfL aims to expand the former service to cover additional National Rail routes in London and the South-East. This could be done through direct operation by a concession-holder, similar to Silverlink, or by a TOC operating under the London Overground brand.