Paul included all believers in the city but doubt he referred to the sects because he was against that.
I just quoted Wallace. He said that. I'm doing what UntoHim said to do in #42...quote some bible scholars.
So a major New Testament and Greek expert believes each town had only one church:
https://bible.org/article/who-should...urality-elders
7The early church
had but one church in each city or town. Hence, Paul's instruction to Titus is to appoint multiple elders in every church.
14 Recall that "elder" = "bishop" and that
each town had but one church.