Aurora bucket list: when do you actually go?

Planning a trip around Iceland next year mostly for this. Everyone says "winter" but that's not very specific. Anyone been and got advice on timing, or on how many nights to allow for weather?
Photo: Carl Young, CC BY-SA 4.0. Source
@wren_holloway · Steady contributor
Allow more nights than feels reasonable. Clouds are the real enemy, more than solar activity.