Auckland's $98 million integrated ticketing system may initially serve only trains and ferries.
A lobby group is urging Auckland Transport to consider a partial rollout of its Hop card by November 30, if only to stem lost revenue from fare evaders on trains.
Buses, which account for 70 per cent of public transport in the city, may not enter the integrated scheme until well into next year. They currently operate a separate system which, despite carrying Hop branding, only works on buses run by NZ Bus.
The problems stem from a dispute between the council transport body and Snapper Services, a sister company of NZ Bus.
Snapper, which lost an $87 million contract for the city's project to French firm Thales, is said to have threatened legal action if Auckland Transport ends a side deal by which it was able to use the Hop brand on its cards.
The body has meanwhile had to delay field trials for the wider scheme, meant to involve up to 2000 passengers by now, until September or October.
A spokesman said Auckland Transport was on schedule for rail and ferry to go live on or before November 30, and was continuing to work with Snapper to join buses to the scheme by then.
Campaign for Better Transport convener Cameron Pitches wants the scheme to be rolled out on trains and ferries in November regardless.
"This is a $98 million project which has been going on for three years - they need to get it in."
He said Auckland Transport was losing too much revenue on increasingly crowded trains under its paper ticketing system, which would be stemmed by electronic gates at main stations under the new scheme.
Trains suffered a 5.5 per cent fall in patronage last month compared with June of last year, and a 2.9 per cent decline in May.
But Mr Pitches feared branding would be a serious problem, given that Snapper had the Hop imprint on its bus cards, leading to confusion if train and ferry passengers were issued with rival tickets bearing the same name.
Labour transport spokesman Phil Twyford, who has successfully called for Auditor-General Lyn Provost to include Snapper's role in the scheme in a general investigation by her office, said he understood it had "no prospect at all" of meeting the deadline.
"This is turning into a disaster for Auckland's public transport system."
Even so, he did not support a partial rollout on trains and ferries.
"Given that buses are 70 per cent of Auckland's public transport system, it doesn't make sense to pilot this without including buses."
HOP CARD COSTS
* Budgeted cost - $98 million. To be shared by the Government (Transport Agency), $56 million, Auckland ratepayers, $42 million.
* Potential alleged extra costs - up to $1.5 million so far.
* Retaining experts to try to fix compliance problems - up to $627,000 a month from August.