[6] After the June 2006 announcement of the Overlander's cancellation, there were proposals to re-instate the Waikato Connection, including from Dave Macpherson, Hamilton City Council's Passenger Transport Committee chairman.

The Overlander's cancellation was subsequently rescinded, eliminating the possibility of using its rolling stock on a new Waikato Connection, but other proposals have remained due to increased vehicular traffic volumes straining road capacity.

These proposals include using the Silver Fern railcars as in the original Waikato Connection, though they were at the time under contract for suburban commuter trains between Auckland and Pukekohe.

[7] An interim proposal from the Rail Working Group in 2011 recommended further assessment of three options: This proposal addressed cost concerns raised by the affected local government organisations by making use of existing rolling stock and infrastructure where possible and avoiding use of the Britomart Transport Centre which, because of capacity constraints, was not available for peak-time arrivals and departures of such a service.

[10] In 2016 the Transport Minister said, when starting work on a parallel section of Waikato Expressway costing over $2bn, "it will be some time before it makes its case economically".

[14] A paper for the same plan proposes a Hamilton–Papakura bus link, taking 1h 20m, 10 minutes faster and much cheaper,[15] at an estimated annual cost of $54,000.

[23] But Tron received fewest positive comments and was the least well liked in focus groups,[24] so Te Huia was then recommended by two Waikato councils.

[30][31] The need to replace some rail track in the Auckland area (including Papakura) where slow (40 km/h (25 mph)) speed limits would otherwise be required had meant that the likely start month has been put back to February 2021.

[48] On 11 July 2023, Te Huia was banned from entering the Auckland metro area by Waka Kotahi after two signal passed at danger (SPAD) incidents (one each in Penrose and Hamilton), forcing the service to terminate at Papakura.

[52] On 17 May 2024, Waka Kotahi New Zealand Transport Agency announced that it would reduce funding for the Te Huia service from 75.% to 60%, commencing 1 July 2024.

ATAP, Auckland's 2018–2028 plan provided for Pukekohe electrification, a third line from Westfield to Wiri and further new electric trains,[55] part of up to $205m a year proposed by government for "transitional rail" spending,[56] which allowed for the possibility of a Hamilton service.

[57] In 2019, the New Zealand government approved a review into upgrading the rail line to accommodate a maximum speed of 160 km/h, which would halve the journey times between Auckland and Hamilton.

It envisages that suburban electric services may extend to Pokeno within 10 years and that, beyond that, the whole route would be electrified and faster alignments be created via the Bombay Hills, around the Whangamarino wetland and east of Huntly.

In 2020 the Ministry of Transport noted that slow and unreliable travel between Hamilton and Auckland is, "limiting the opportunity to strengthen economic integration and productivity of the two metropolitan areas.

The Ministry also found that car dependency put a disproportionate cost on the poor and hampers efforts to cut greenhouse gas emissions and accidents.

[69] Therefore in July 2020 the Ministry was instructed to develop the next stages for train travel in greater detail,[70] including a possible extension of Hamilton to Auckland rapid rail to Tauranga.

All four options include a new underground rail station in the Hamilton CBD[72] and all allow 32 minutes for the 35 km (22 mi) between Papakura and Britomart.