I will provide info on the unit as the OP hasnt. The British Rail Class 710 Aventra is a type of electric multiple unit passenger train currently being built by Bombardier Transportation for use on the London Overground network. The trains are part of Bombardier's Aventra family. The contract to provide 45 four-car trains was awarded in July 2015 and the trains were originally due to enter service in May 2018, although introduction was delayed until May 2019. The interior of a Class 710 In service 23 May 2019 – present Manufacturer Bombardier Transportation Built at Derby Litchurch Lane Works Family name Aventra Replaced Class 172 Class 315 Class 317 Class 378 Constructed 2017 - 2020 Number built 54 units Formation 4 or 5 carriages per unit Capacity 4 car - 189 Seats, 489 Standing 5 car - 241 Seats, 641 Standing[1] Operator(s) London Overground Depot(s) Willesden TMD Ilford EMU Depot Line(s) served Gospel Oak to Barking line Romford–Upminster line Lea Valley Lines North London line West London line Watford DC line Specifications Train length 5 car - 102.85 m (337 ft 5 1⁄4 in) 4 car - 82.86 m (271 ft 10 1⁄4 in) Car length 19.99 m (65 ft 7 in) 21.446 m (70 ft 4 in) (End cars) Width 2.772 m (9 ft 1 in) Height 3.76 m (12 ft 4 in) Maximum speed 75 mph (121 km/h) Weight 4 car AC Unit - 144 t (142 long tons; 159 short tons) 4 car DV Unit - 151 t (149 long tons; 166 short tons) 5 car DV Unit - 182 t (179 long tons; 201 short tons) Electric system(s) 25 kV 50 Hz AC Overhead lines 750 V DC third rail (710/2 only) Current collection method Pantograph (AC) Contact shoe (DC) Bogies Bombardier FLEXX Eco Braking system(s) Knorr-Bremse RZKK and RZTS with 2 actuators per axle Safety system(s) AWS / TPWS Coupling system Dellner Track gauge 1,435 mm (4 ft 8 1⁄2 in) standard gauge In 2012, Transport for London announced its intention to procure a fleet of new, longer DMUs, as the Class 172 units then in service were unable to handle the passenger demand, causing overcrowding throughout the day. TfL issued a tender for manufacturers to supply eight three- or four-car trains.[3] However, this proposal was subsequently shelved when the Government announced in June 2013 that the Gospel Oak to Barking line would be electrified,[4] with proposals instead to purchase a fleet of new EMUs. TfL invited expressions of interest for a total of 39 four-car EMUs in April 2014, with 30 required for the Lea Valley Lines, eight for the Gospel Oak to Barking line, and one for the Romford–Upminster line - all to replace older Class 172, Class 315 and Class 317 trains.[5] Since then the planned procurement was increased to 45 four-car EMUs, with the additional six units intended for the Watford DC Line. The intention is that the five-car Class 378 trains currently used on the Watford DC line will be cascaded back to the North London line and East London Lines to allow for strengthened services. TfL issued an Invitation to Tender (ITT) in early 2015, and in June 2015 announced that Bombardier had been awarded the contract to build the new trains.[6] In July 2015, TfL announced that it had placed a £260m order for 45 four-car Bombardier Aventra EMUs, (with an option for 24 more four-car units plus further option to extend some or all units including option units to five cars). These are similar to the Class 345s that will be used by Crossrail, for use on the Lea Valley Lines and the Watford DC line, Gospel Oak to Barking line and Romford–Upminster line, from 2018, to be known as Class 710.[7] The units will be delivered in two sub-classes; an AC-only version for use on the Lea Valley Lines and Romford–Upminster services, and a dual-voltage version for the Watford DC and Gospel Oak to Barking line services. Both versions will have all-longitudinal seating after the plan to have some transverse seats on the AC units was dropped. The AC only version will be maintained at Ilford EMU Depot and the dual-voltage units at Willesden TMD.[8] In 2017, Transport for London put forward a proposal to procure nine additional Class 710 units to be used as capacity enhancers. These would cover 42 of the 249 additional vehicle options, and would be formed into three 4-car sets, one which would be for use on Watford DC line and two for the extended Gospel Oak to Barking line to Barking Riverside, and six 5-car sets for use on the North London line and West London line, allowing a cascade of Class 378 units to increase services on the East London line.[9] On 25 April 2018, the Islington Gazette reported that the trains would be introduced three months later than scheduled due to delays in their testing.[10] On 20 June 2018 the Barking & Dagenham Post reported that the trains would be in service by November 2018, "almost 18 months later than planned".[11] In November 2018, TfL said that they hoped the units would be in service by December 2018,[12] however, further delays prevented this.[13] In January 2019, TfL announced that three Class 378 trains would temporarily be deployed on the Gospel Oak to Barking line while continued problems with the Class 710 units were resolved,[14] since leases on the existing Class 172 stock running on this line would come to an end before the 710's likely introduction into passenger service. In April 2019, the Office of Rail and Road approved the use of the Class 710, with restrictions.[15] On 22 May 2019 TfL announced that approval had been gained for the Class 710s to enter passenger service. The first two units entered service on the Gospel Oak to Barking line on Thursday 23 May 2019 and the remaining six were in service by August 2019, with the first unit entering service on the Watford DC line on 9 September 2019. The first units on the Lea Valley lines entered service on 3 March 2020 after a first attempt on 24 February 2020.[16] The services on the Romford-Upminster line started on 5 October 2020.[17] As you can see, these units run along the Watford DC lines, which means you add them to the Bakerloo lines among other routes (providing AWS and Yellow signals are added to the Bakerloo, which cant be hard) this would also be a great time to have a shot at the first route extension to Watford to allow longer runs for the Class 710, DTG would also need to allow the use of the other platforms at Queens Park and Wilsden Junction (one of the two) and maybe model Kilburn High Road too.
Maybe they could add the London Overground Watford DC line and then add this train as sort of a extension for the bakerloo line. Everybody who owns tsw2 will have the BKL so a extension to add the Watford DC line would be a no brainer
