Additionally, NightRide services are prefixed with N Some routes have a suffix to their route numbers instead of a prefix: N - Overnight services for the routes concerned with some minor variations (used since 2018) X - Express service equivalents for the routes concerned used by Hillsbus (services via Lane Cove Tunnel), Transit Systems (regions 3 and 6), State Transit (region 7, 8 and 9) and two Forest Coach Lines routes in region 14 Any other letter - Used by some operators to denote the destination of routes with more than two termini. For example, the suffixes W and K are used by Busabout to denote variants of routes 884 and 883 that service Wedderburn and Kentlyn respectively. State Transit and Transit Systems Region 6 school bus services are suffixed with N (Region 8), S (Region 6), E (Region 9) and W (Region 7). However, bus destinations boards do not show the suffix due to technical limitations. Rail and ferry replacement bus services Rail replacement bus services in Sydney replace or supplement train services, but charge train or metro fares. Ferry replacement bus services also sometimes replace F3 Parramatta River services between Parramatta and Rydalmere when there is low tide. Station Link From September 2018 to May 2019, Station Link bus services replaced rail services between Chatswood and Epping, while the Epping to Chatswood rail link was converted and upgraded to metro services. The main service SL1, operated frequently throughout the day, stopping at all stops between Chatswood and Epping. The other services SL2 - SL7, operated only during weekday peak hours. Fares on these bus routes were charged at train rates. The services were jointly operated by Transdev NSW and Hillsbus. Two weeks before its cessation, over 4.3 million trips had been taken on Station Link. North West Night Bus From 26 May to 5 November 2019, North West Night Bus operated on two supplementary late night bus services, NW1 and NW2, to supplement the Metro North West Line metro operations on Sunday to Wednesday nights. They are successors to the Station Link, which was discontinued due to the opening of Sydney Metro. Metro fares were charged on these bus routes. Like Station Link, both Night Bus services were also operated by Transdev and Hillsbus. Route 535 The T6 Carlingford Line ceased operations on 5 January 2020, and a replacement bus service, route 535, commenced operations on the same