I think most people are scared of the distance in between France and UK, while a flight from Coquelles (for example) to London shouldn't take more than 10-15' and if you consider that British pilots will be waiting over Cliffs of Dover, then I think that action will be instant as soon as both sides take combat height.
For the rest there are always DF arenas and of course time compression which is an excellent option to save time.
Nevertheless, in due time, we'll see everything. People will definitely create airstart campaigns among other types, so...no worries for anyone
