The core system stays the same, with small additions at the edges of the season. Travelling in November or March you might want a warmer optional midlayer, heavier gloves or mittens, and more face protection, because more snow, lower sun angles and colder wind are all possible. Mid-summer travellers still hit snow, rain, strong wind and cold Zodiac rides, so nothing essential comes out of the bag.
Don't try to forecast a voyage months ahead. Pack one flexible system with a warm maximum and a light minimum, then let the daily clothing briefing from the expedition team decide what you actually wear.
The temperature difference across the whole season is about one extra fleece layer, so this is a smaller adjustment than people assume. What changes more is how much time you spend stationary in an exposed Zodiac, and that's driven by the day's plan rather than the month.