I have far less experience facing the BI in jets compared to props but here’s my take based off the numbers.
Even at low altitude, the BI can maintain around 500 MPH TAS at only 30% throttle, which will last about 20 minutes from a full tank, and it can accelerate from takeoff to this speed in seconds. Early jets, especially at 7.0 and below, have poor acceleration, and top speeds not much faster than this. I think that in a 6.0 - 7.0 or 6.3 - 7.3 match on normal sized maps, if the BI is aggressive early in the match by flying directly towards the enemy AF in a high speed, shallow climb there will be basically nothing the jets can do. The BI will reach them with a speed and alt advantage far before they have time to accelerate, and can just start tearing them apart. The more they maneuver trying to avoid or kill the BI, the less chance they have of catching it and the more vulnerable they will be when the rest of the BI’s teammates arrive. The BI is outright superior to any 7.0 jet imo.
For fighting jets which are significantly faster than the BI, like 7.7s or higher, I think the key will be the BI’s rate of climb. You can’t get BnZed relentlessly by an enemy who is far below you, even if they are going 100 mph faster. Sure, the BI would not be able to catch such an opponent without ripping, but other 7.0-7.3 jets would have the same problem in the same situation. In reality, a Meteor Mk. 3 or F3D could only dream of finding itself in a situation where, having been able to so effortlessly outclimb all Mig-15s and Sabres while still being able to go 550 mph TAS, it now can’t dive on them without ripping unless they slow down.
I think from this position at altitude over the combat area, the BI should conserve its fuel by throttling down to maintain ~300-350 mph, and dive opportunistically on anyone who gets too slow. If the enemies are staying fast, stay high. If they are slow, get in there and kill them. Maximize your opportunities by staying just high enough that the enemies cant reach you without exposing themselves for you to attack, but not so high that you accelerate uncontrollably when diving in and/or they have time to dive/accelerate away. This is somewhat similar in method but drastically easier than playing the Ki-200 in an uptier against supersonics.
The BI would suffer from BR compression at 7.0/7.3, but it would still be in a better position than many 7.0 or 7.3 jets. Let’s say you climb up to 20000 feet, and burn through half of your fuel doing so, such that you have only 1 minute left. At 20% throttle, you can still fly at over 500 mph for over 25 minutes. Due to being a rocket the BI benefits massively in fuel economy at high altitude, since drag decreases with increasing altitude, but unlike a prop or jet, thrust actually increases. This makes the BI’s physics-defyingly efficient rocket engine even more insane.