Nine bids were received for the Seletar bus package tender, which closed yesterday at noon.
Among the bidders were Singapore's Woodlands Transport, National Express from Britain and Australia's Busways, as well as two consortiums: Kumho Buslines-Tian San Shipping and Travel GSH-Jiaoyun Group.
Travel GSH and Tian San are local firms, while Kumho is from South Korea and Jiaoyun is from China.
Four of the bids were from existing players SBS Transit, SMRT Buses, Go-Ahead and Tower Transit.
Go-Ahead, which won the Loyang tender in November last year, put its name in despite facing a shortfall of bus drivers.
The Britain-based company last month saw 20 of its bus drivers quit over its practice of interlining, which requires them to drive multiple routes.
Now everybody will have to convince the LTA that their business plans are actually realistic.
DR WALTER THESEIRA, SIM University economist, on the tender deadline being extended to give bidders more time to tweak their proposals to scale back interlining.
To make up for the shortfall, Go-Ahead entered into an arrangement with SBS Transit and SMRT Buses, where the two loaned a total of 40 bus drivers for two months to the British firm.
The loan arrangement is expected to end next month.
When asked about its prospects of winning the new tender, Go-Ahead would say only that it awaits the decision of the Land Transport Authority (LTA) and that it is "continuously recruiting candidates who are keen on becoming bus captains".
It is believed that the deadline for the tender, which opened in June and was originally slated to close on Oct 6, was extended to give bidders more time to adjust their proposals to scale back interlining following the incident.
"Now everybody will have to convince the LTA that their business plans are actually realistic," said SIM University (UniSIM) economist Walter Theseira.
Dr Park Byung Joon, UniSIM senior lecturer in urban transport management, said the spate of resignations would not help Go-Ahead's chances.
The winning firm will operate the upcoming Seletar bus depot, scheduled to be completed in the third quarter of next year, and have 26 bus routes operating from the Ang Mo Kio, Yio Chu Kang and Yishun interchanges.
The tender is the third under the new bus contracting model, where the Government owns all fixed and operating assets while operators focus on meeting service standards.
Anglo-Australian firm Tower Transit clinched the first bus tender for the Bulim package in May last year with a bid of $556 million, which allows it to operate 26 services in the west of the island.
The second package for 25 services in Pasir Ris and Punggol, operating out of the Loyang bus depot, was awarded to Go-Ahead for $497.7 million last November.
The Seletar tender is expected to be awarded in the first quarter of next year.