A couple of notes on YHWH vs. NT:
1, The Jews stopped to pronounce the name before 1st century. Why we cannot find any criticism of this custom in the Bible? Majority of Septuagints used Kurios instead of the tetragrammaton. But there is no discussion of how bad is to use 'Kurios' instead of YHWH anywhere in the Scriptures. So it seems the 1st Christians accepted usage of Kurios.
2, Standard WTS claim somebody replaced YHWH in the centuries after Jesus: I have not seen any hard facts provided by WTS supporting this theory. Historic science simply does not work this way - I cannot simply state something happened but I need to provide proofs or strong indications for it.
3, Christian heresies in the first centuries are documented - Docetists, Ebionites, ... We have also good traces of Gnosticism, discussions with Jews, various discussions among Christians. But we do not have any trace of discussion of Kurios / YHWH. Why?
4, At the end of 1st century there was apprx. 1 million of Christians spread across the whole Roman world. How did somebody manage to replace YHWH with Kurios in this geographically dispersed realm? How did these conspirators manage to leave no trace of this big change?
5, George Howard and WTS - GH says a) it is a theory b) he is not supporting 237 places changed by the WTS. Try to google him.
6, How is it possible we do not know exact form of the name? If it was widely used then at least one Christian or even enemy of Christians would use it - but there is no form preserved in Greek / Latin form. Why did not secular historians from that era say 'Christians... those people using the name...'?
7, This step done by the WTS is not a small thing - it is completely changing meaning of some scriptures - for example Rom. 10, or Acts 7:59,60