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Some more to consider and overload the thought process with, this time incorporating Pol's idea about including "2021" in the title.

WOFF: The Great Air War 2021
WOFF: War in the Air 2021
WOFF: Rise to Glory 2021
WOFF: Between Heaven and Hell 2021 (a nice throwback don't you think)
WOFF: Heaven High Hell Deep 2021

And/or simply add "2021" to the following, some of which I mentioned earlier.

WOFF: The Sky Their Battlefield
WOFF: A Gathering of Eagles
WOFF: The High and the Mighty
WOFF: Fire in the Sky
WOFF: Endless Flight
WOFF: Tumult in the Clouds (Fullofit, this is the 'PG' adjusted version)

You could also place the "2021" ahead of the new title if the flow is better, such as this - WOFF: 2021 Between Heaven and Hell; or as this - WOFF 2021: Heaven High Hell Deep.

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