Importers and lorry drivers complained of delays yesterday as the main cargo operator began handling all freight at Chek Lap Kok. One driver said he had waited six hours for a delivery that would have taken 90 minutes at Kai Tak. Hong Kong Air Cargo Terminals Limited said that although it had begun handling all inbound and outbound cargo at SuperTerminal 1, 100 staff and 10 per cent of freight still remained at Kai Tak. The backlog would not be cleared until tomorrow evening, it said. The company was forced to switch operations back to Kai Tak because of a computer breakdown when Chek Lap Kok opened. Managing director Anthony Charter said the company faced greater challenges in the 'critical months' of September to November - the peak season of the air cargo business. But he said the company was 'fully confident' staff and government officers would quickly become familiar with the new environment. Deputy managing director Yeung Kwok-keung said: 'Once everything is moved back to Chek Lap Kok, we will have more time to devise improvement strategies.' He said lorry drivers were having to wait because Monday was traditionally a heavy day and some staff were still at Kai Tak. One import firm said a 700kg shipment of US beef which arrived on Friday morning could not be picked up for more than 12 hours. 'They said last week that things would be back to normal [today]. I doubt things will be fixed this week,' the importer said. Legislator Lau Kong-wah said there was no guarantee another breakdown would be avoided and warned that contingency plans should be drawn up. 'As this has been such a bad experience there must be contingency plans, even if it just involves a quick and smooth transfer to Kai Tak's terminal,' Mr Lau said. The company said it had lost about 10 per cent of its business to neighbouring airports.