A continued sortie (refuel/rearm) as it currently stands appear to just extend that sortie. Which I think is very wrong. If you land, that's a sortie, agreed? Apparently you just keep on going and could end up with a 40 kill sortie, if you live long enough. I myself managed a 12 kill double sortie(??) where I landed and refueld once. I ended up bailing out and judging by the impact(or lack there of) on my score, I'm guessing the first 7 kills of the first sortie did not count as a landed 7 kill sortie. Maybe I'm wrong? BUT, IMO once you land, that's a sortie and the streak should end(in the kill buffer). In theory it's good if your field is under attack and your hangars are down(but at that, your acks probably are too so refueling/rearming is more dangerous than just .esweet to another field).
Your mileage may vary.
-SW