The arrival of the Alstom Class 334 "Juniper" EMUs to the SPT fleet in 2002 allowed the last of the elderly Class 303s to be withdrawn and the Class 314s to be cascaded to services on the Cathcart Circle and Inverclyde Lines. For a number of years, Argyle Line services were consequently operated by a combination of Class 334s and BREL Class 318s displaced from services on the Ayrshire Coast Line. However, the Class 334s have mostly been transferred from December 2010 to operate services on the Airdrie-Bathgate Rail Link, with only occasional services being rostered for these units.