Lal, there is a contradiction between those two posts:
#44675
…As I remember, our solar system (cakkavāla) is one of a 10,000 cakkavāla in a cūḷanikā lokadhātu. …
A Buddha can arise in only one cakkavāla in a cūḷanikā lokadhātu.
#44711
…. At marker 4.3: “cūḷanikā lokadhātu” is a SMALL cluster of a thousand such cakkavāla ….
…Each “mahāsahassī lokadhātu” can have only one Buddha at a time. But there can be Buddhas in other “mahāsahassī lokadhātu” even at this time.
As per the sutta AN 3.80 a mahāsahassī lokadhātu contains 1000 x 1000 x 1000 = 1 billion cakkavala.