Knockholt's a peculiar station because nobody much lives anywhere nearby, and because it lies on the very edge of the capital - the platforms are in London, but the two bus stops outside are fractionally in Kent.
Knockholt's also a peculiar station because isn't served by a London bus, only by the 402 from Bromley to Tunbridge Wells, which is run by Arriva Kent & Surrey Ltd. If you have a Travelcard or Bus & Tram Pass you're allowed to ride on the 402 for free, at least as far as Knockholt village, and if you have Oyster you're allowed to travel for a "discounted cash fare", but it's not a TfL service. TfL does run buses to Knockholt, the R5 and the R10, but they run really infrequently, and don't go within a mile of the station. There's also the R7 which I mentioned yesterday, but that doesn't stop anywhere near the station either, the closest stop being outside the Bo-Peep pub about a kilometre away.
And very soon Knockholt station won't be served by any buses at all, because Arriva have just applied to cancel their London Service Permit on route 402. From 23rd July all service between Bromley and Dunton Green will be withdrawn, and the 402 will run on the remainder of the route.... in Kent only. The village of Badger's Mount will lose its bus service completely, and residents of Halstead and Knockholt won't be able to take the bus to Sevenoaks any more. Greater London residents won't be troubled, they have alternative TfL services within the capital, but those on the Kent side won't be so lucky, and Knockholt station will become bus-less overnight.