Before/After Time At Dusk/Dawn

I’d like to see a feature for the timers, in my case the outdoor plug-ins, to be able to set a On/Off time not only in relation to Dusk/Dawn but to be able to have the On/Off time either before or after a certain amount of time.
For example, instead of just have my lights turn on at Dusk, be able to set 30 minutes After Dusk.
And instead of just off at Dawn, be able to turn them on 30 minutes Before Dawn.