What procedures are used for midair refueling without air supremacy? One of the major themes of the answers to (and comments on) my earlier question about tankers not having ejection seats is that tankers are used only in environments where the threat from enemy aircraft is minimal or nonexistent; for instance:

...Tankers are big, slow, and devoid of defensive measures because they don't need any of that. They're used from a very safe distance, and if there is a risk of enemy air power, friendly air power runs interference...
...Primarily because tankers and transports are being operated in non-combat environments or safely benhind [sic] the front lines of a battlefield so ejection seats are not absolutely necessary for crew survival...
...In the end, it's unlikely a refueler will be shot down. Refuelers are generally only flown in areas where we have control of the airspace, or reason to believe that we are well away from enemy fire...
...A refueler will never be out on it's own. Like I said, they expect aerial supremacy, and have fighters run interference for them. If a fighter is closing on a refueler, full of tens of thousands of pounds of jet fuel, they're already gone...
...For the United States, the assumption is that we will always be able to have air superiority in some area due to overwhelming firepower and technology (though area that may be further away from the battlefield, making the tanker less effective, though still more efficient than landing.) The tanker would never fly directly over the combat zone unless we had air superiority there, as it's quite simply a sitting duck - they have basic defenses though, as you can never guarantee air superiority...
...Tankers are not supposed to be flying in any area where they would be taking enemy fire, so an evacuation situation would essentially be a freak event. Most of the scenarios where a tanker would be attacked have a low survivability anyway...

However, it is quite conceivable that combat aircraft might require mid-air refueling in a situation where air supremacy – or, worse, even air superiority - cannot necessarily be attained (for instance, in a full-scale war between the United States et al and China, or, less likely, Russia), and where restricting tanker aircraft to uncontested airspace would put them so far away from the target(s) being attacked as to be useless.
What are the procedures that are followed for refueling combat aircraft in an environment of mere air superiority or (worse) air parity, rather than air supremacy?  Are the types of tankers used restricted to only those converted from bombers (and thus already possessing both ejection seats and greater maneuverability compared to tankers based off of civilian designs)?  Do aircraft rely solely on buddy tanking (thus tying up most of one’s combat force with tanker duty)?  Are tankers escorted by dense enough swarms of fighters to be able to bull their way through any airspace, no matter how hostile (thus using up most of the tanker’s fuel merely to sustain its own escorts)?  Or do the ministries of war of the countries involved simply resign themselves to having to mass-mail “we regret to inform you” letters?
It's actually a problem the US Navy at least has been considering - with improvements in anti-ship missile capability (such as China's Dong-Feng 21D) meaning that carriers are at risk at ranges approaching 900NMi having to keep the ships out of range is taking a large chunk out of the effective range of aircraft such as the F35C which has a range of 1,200NMi and refuelling a "stealth" aircraft with a conventional tanker plane sort of defeats the point.

As a House Armed Services Committee report noted:


  The committee notes that the aircraft carrier air wing has been optimized for striking power and sortie generation and believes that it may not be configured to support the long-range strike required by current and future threat systems. While the introduction of the F-35C will significantly expand stealth capabilities, the F-35C could require increased range to address necessary targets. The committee believes that several options could be used to address this issue to include developing a stealth tanker capability, improved engine technology, or to develop and procure a strike capability that is purposely built to strike at increased range.


The current proposed answer to this is the MQ-25 development of which was approved by the US Navy earlier this year for service in 2024.

The MQ-25 is intended as an un-manned tanker with stealth capabilities delivering fuel for 4-6 aircraft at a range of ~500NMi, as a) a stealth aircraft itself it will be harder to detect and intercept and b) as UCAV if it does get shot down there's no need to think about ejection seats or any other mechanism to protect the crew.