Do I instantly get buying power after selling covered calls?

Quick question, if I sell covered calls, then I instantly get new buying power based on the premium I collected and at that point can purchase more shares, right? For example: I spent $1.72 on 3000 shares, so $5,160 30 of them go for $75 each, which amounts to $2,250 (which I collect in premium). Then if ATOS goes to $20 per share, the stock I'm holding could be called away, and if it is, I get $9 per share, which amounts to $27,000. I keep the $2,250 premium I collected, and now I am sitting at $29,250 from the $5,160 investment and $24,090 in profit. But, let’s say ATOS only reaches $7 per share by July 16, then I keep my shares and the $2,250 I collected. If I do that again for another round and the penny stock doesn’t hit the next strike. All my shares are free. If ATOS goes to nothing, the most I would lose is $5,160 minus the $2,250 I collected. So, therefore, the $2,910 would be my max loss on the trade, and I've minimized my risk. However, if I sell calls and take that $2,250, I can buy almost 1,000 additional shares, sell 10 calls on the new shares, and collect $750. I can then buy 300 more shares with that premium and sell 3 more calls, making $225. Now I own 4,300 shares in total and have collected $3,225 in premium on top of it and hold shares worth $13,932. If ATOS never hits over $9 by July 16, then I end up with all my 4,300 shares, keep the $3,225 in premium I collected, and I can start selling covered calls all over again; Taking the $3,225 and buy whatever ATOS is trading at that point and sell calls on the entirety. Is any of my logic out of whack?