Quick questions: javelins with dueling style and natural weapon proficiency

[ThorOdinson]

If it’s wielded in one hand.

Per your own admission, the weapon is considered wielded in one hand until the attack is complete.

I have never stated or admitted that. In fact . . .

the weapon is considered wielded in one hand until the attack is complete.

I am once again indicating here (and I have indicated in the past) that the above statement is a house rule on your part. That rule is not in the PHB. I don't allow house rules.

But feel free to prove me wrong by finding support for your house rule in the PHB.

If you can find support in the PHB that players are to follow this house rule you have made. . .

the weapon is considered wielded in one hand until the attack is complete.

If you have rules support for the above house rule then please share it. We can then treat your argument as RAW.