I want to only record my local news at 10.30 pm but with series link it records all daytime one as well so I have to spend time deleting them. I had sky before which let me record just the one I wanted so why can't virgin do that
An SL will record the first available broadcast of any given show, sounds like there's insufficient EPG data to uniquely identify the 22:30 broadcast so it's defaulting to the "I'll get 'em all just in case" situation you find yourself in.
A manual recording for Monday - Friday @ 22:30 - 23:00 on BBC1(or whichever channel) is likely the only way of ensuring you get only what you want.
Just like any other SL you can set it to retain only so many episodes, set to 1 will leave you with just last nights broadcast (or as many episodes as you want of course).