I have just booked a RTW trip departing in April (courtesy of the excellent advice, guidance and work from nuffnuff77). The route I have (plus the positioning flight to/from Oslo with an overnight airport hotel stay which fits as a BAH) will give me some 21,000 nTPs so that I can secure Gold status until end of March 2028, and allow me to visit the places that I have on my 'To Go To' list.

If you are considering a RTW itinerary or some complex routing then I would heartily recommend seeking out his advice.

P.S.: Apart from the positioning flights to/from Oslo (to use a BAH) none of the 12 flights on my itinerary from Oslo are with BA, thereby securing 50% mileage nTP accrual.