This photograph dates from 2016 and there have been major changes to the bus service since then. Also It is planned that there will be a new  BusConnects Core Bus Corridor from Clongriffin to the City Centre.

https://busconnects.ie/media/2103/01-clongriffin-to-city-centre-preferred-route-301020fa-web.pdf

In a statement, Dublin Bus said: "From Sunday 21 October 2018 we are pleased to announce that Route 15, Route 15a and Route 15b will be more reliable with additional departure times, more frequent services and earlier start times each morning.

In November 2021 Dublin Bus announced that the 15, which runs from the Ballycullen Road, through the city centre and onto Clongriffin, will become a 24-hour service. From Sunday, December 1, the daytime frequency on the 15 and 41 will improve, with the service running at a 30-minute frequency . According to a statement released by the National Transport Authority (NTA), the fare structure will remain unchanged, with no additional customer charge for travelling late at night.