I never go there at lunchtime, always in the evenings. The throughput of evening customers is high enough to ensure that nothing sits around for long. Indeed, if you want anything other than cod, they will only cook it to order.
One of the things you need for good fish & chips is a high turnover so everything is fresh. Best i've had lately was an excellent skate & chips in Bankers on a Friday night. (Although i'm sure their homemade tartare sauce used to be better)