2 Tim 4:3 refers to the 16th century revoltThere's no reason to think heresy believed by religious leaders among the Jewish people, couldn't happen in NT churches.
The NT even shows how congregations become corrupt,
Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils; 1Tim.4:1
For the time will come when they will not endure sound doctrine; but after their own lusts shall they heap to themselves teachers, having itching ears; 2Tim.4:3
Yes but not the universal church on matters of divine faith and morals
Truth is divine and immutable and cannot be reformed
The church is divine and cannot be reformed
It is already a reformation of the mosaic covenant heb 9:10 that’s why the one true new covenant church has so many similarities to the mosaic covenant example: the three fold priesthood
High priest
Ministerial sacrificial priesthood
Common priesthood of the baptized believers.
Thanks