Under SEC rules if you had held the first stock for more than three days you should be able to buy another stock immediately but you would not be allowed to sell that second stock until funds from the first transaction had cleared (three more days).
That is not what it says in your link regarding cash accounts. There is no requirement that the first stock be held for 3 days before sale, only that it is in the account and fully-paid for before it is sold. IOW, if you have $10K cash in your account and no other assets and you buy $10K of a stock on Monday, you can resell it on Monday, no problem because the cash in your account was available to pay for the stock in full immediately. BUT while you can buy another stock on Monday with those uncleared funds from the first sale, you cannot sell that second stock until it is fully paid for when the first funds clear, which would be 3 days later.
Newly