I don't think the time of year really matters but light levels - and water clarity - have a lot to do with feeding habits.
If the pit's cloudy, ie still being worked, they'll almost certainly feed all day if you can find them. Coloured-up areas - near wash-ins, or the windward bank on clay and sand pits; where the water will colour up in a good blow, are worth going for, esp if bait fish are attracted to the area by stuff getting stirred up.
If it's clear, you'll either find them in the deeper water by day or near anything which gives them shade or cover. Clearer conditions probably mean dull, overcast weather, dawn and dusk or even all-nighters are needed to find them.
By day try drifter fishing for them with livies or paternostering them on the sides of any deeper drop-offs etc.
Get the bait up off the bottom either way unless it's totally brass monkeys weahtehr, because it can be seen from further away and they'll happily come up in the water to have a pop at it.
They're a very mobile fish so if they aren't in front of you you've either got to keep moving till you find them, or sit tight in the hope they'll show up sooner or later.
If I had to use deads I'd go for float legering them, or popping them up just off the bottom. It's far more sensitive than a leger set up and you'll hit a lot more takes.
It also cuts down the amount of bank sticks, bite alarms etc you have to carry, meaning you can be more mobile.
Don't scale down too far - there's no point. A lot of these so-called dropped takes are down to the way they feed, rather than being finicky.
They'll often hit a bait and kill it and then just swim off and leave it - maybe it's an instinctive thing.
Tiny trebles and small baits are a recipe for deep-hooked fish, especially after dark.
At night don't be afraid to fish very close in - literally just over the marginal shelf - as they'll come right in close looking for the small stuff.