If Tether untethers there will be a rush to other assets, pushing them higher.

Shorts denominated in USDT will get absolutely decimated, pushing other assets higher.

Exchanges using Tether will enforce a maximum withdrawal, pushing other assets higher.

Smart money will buy USDT at a discount once their reserve details are made publicly available. If it's FUD they'll make an absolute killing.

There's 3 possibilities here: 1. Tether is completely backed 1:$1 (highly unlikely) 2. Tether is partially backed, the reserves are greater than the outstanding 3. Tether is partially backed, the reserves are less than outstanding

Only 3) will have a downward price correction. If they've been buying BTC like everyone here has suggested then 2) is the most probable, since you know BTC is at yet another ATH.

If it becomes public that tether has excess reserves, the FUD will disappear silently. Worst case Tether says they will slowly sell off to reach 1:$1 over the next 12 months.