How far does the business advanced hold a full bar status?
Are you asking what distance can be flown with BA seat for it to hold 5 star (5 green bars) rating?
I don't know, but you can try and test. That's what I am doing with a lot of things.
Check it out at seat configuration. You can click "rating" of your seat configuration for each type of aircraft and find it out. You would need to consider that the rating may be subject to differences in final rating that appears in ORS.