USDT is an option but
it is NOT a good option though.
tether is a convenient altcoin with a nice feature that stays at $1 but at the same time it is not risk free. there is a high chance that the price can fall down, the company that backs this coin can even go down (bankrupt or something) and that can put an end to this coin and your money can go up in smokes.
altcoins are not valid options either. they go down if by any chance bitcoin goes down. your only option is to go back to fiat if you think bitcoin may go down.
and remember that no matter what you do, you are still taking a lot of risk. because there is a better chance that bitcoin rises a lot more like the previous time fork happened. you sell at $5000 and come back after the fork just to see price at $7000+