Services operate every 30 minutes between 10pm and midnight, and then every hour between midnight and 5am on weekdays
Tim Gaston, director of public transport services with the National Transport Authority (NTA) said the lack of available drivers has held up their timetable in terms of the redesign of the city’s network.
"The network redesign is moving along almost to plan; we've had to slow down a little bit this year - even during Covid we introduced two phases as well,” he told Newstalk.
"So we have actually kept the network redesign running pretty well.
"Bus companies at the minute are all suffering the same driver shortage, which is why this service is a little bit later than we had hoped - there is a general driver shortage across the country.”
He was speaking as G-Spine routes of G1, G2 and Route 60 will be operated by Dublin Bus from Sunday October 16.
This will see services operate every 30 minutes between 10pm and midnight, and then every hour between midnight and 5am on weekdays.
The G1 and G2 are set to operate twice as frequently on the spine section between Ballyfermot and the city centre.
Route 60 will also run every 60 minutes between 5:00am and 11:00pm on weekdays.
Additional peak journeys will be included for Route 60 during the school term, for both the morning and evening, between Cherry Orchard and the city centre.
Mr Gaston told Newstalk Breakfast they hope to rollout more phases next year.
"These services serve the west of Dublin," he said.
"What we're introducing is the fourth of 11 phases of the BusConnects network redesign in Dublin.
"It's the G Spine and Route 60; and they run from the west of Dublin into the centre."
He explained: "The two spines are 24 hours - G1 and G2 - they run all through the night, seven days a week.
"This is now the 10th or so service we've introduced along this programme that runs 24 hour."
"Next year we hope to launch another three or maybe four phases of the network redesign, so we are keeping that initial moving along", he added.
The introduction of the new routes will coincide with the removal of routes 79, 79a and the Western part of route 40.
Route 40 will also no longer serve Liffey Valley Shopping Centre to the city centre, as this section is being replaced by the new G2.
Passengers can also use the G1 to interchange with Luas Red Line services at Red Cow, Connolly Station and Spencer Dock.
It will also see an interchange with Irish Rail services at the Park West and Cherry Orchard station.
And in the city centre, passengers can interchange with Bus Éireann services at Busáras.