Similar to radar in 1.02, ships with spotting aircraft should have a chance to cause a day battle to start at a longer range than normal. Probably variable based on number of aircraft in the engaging forces and the range/speed of spotting aircraft. Spotting aircraft should start deployed and one side would be likely to receive a spotting report soon.
This should also apply to LBA scouting from airbases. So day raids would naturally start very far away from their targets as time went on(though you'd need increasingly huge numbers of scouts at an airbase for it to actually force a battle). That would mitigate the current issue where a small battle spawns in an enclosed waterway and the force is instantly mobbed by hordes of dive bombers.
In terms of how far, I'd go with the square root(i.e. a circle) of the number of planes times the plane speed, capped at the maximum range of the aircraft involved. So even a few planes would be likely to significantly extend battle ranges, but even huge numbers couldn't make them too many times bigger.
Here's a post about the same issue from the original suggestions thread: nws-online.proboards.com/post/45526/thread Idea would be to run search patterns in a "pre" phase that might roll start positions back (in time and location) to when spotting actually happened.