Compare and contrast that group of saints with the ALREADY (PRE-TRIB!) RESURRECTED group so noted in Rev ch 4 & 5 the "Elders" aka Church.
THAT, dear sir, is an example of the MULTIPLE COHORTS (and there are more than two!) that constitute the ORDERS AND RANKS of the FIRST RESURRECTION. Old Testament saints are ANOTHER unique group with a unique ORDER AND RANK!
Rev 6:11
Then a white robe was given to each of them; and it was said to them that they should rest a little while longer, until both
the number of their fellow servants and their brethren, who would be killed as they
were, was completed.
Rev 7:9
After these things I looked, and behold, a great multitude which no one could number, of all nations, tribes, peoples, and tongues, standing before the throne and before the Lamb, clothed with white robes, with palm branches in their hands,