Early warning is more plausible than air refuelling

Could Britain field airborne early warning or practical aerial refuelling before a delayed war?

Airborne early warning is the more plausible development, while aerial refuelling remains less likely despite active interest.

Carrier and fleet aviation had already used visual airborne warning roles in exercises and operations. That makes a dedicated early-warning development a logical direction as radar improves. Aerial refuelling was also under consideration, with much less chance of becoming practical in this period.