The last few days on the market has seen a stella performance by the "safe' high yielding stocks. If we look at CBA, from early June, we can see that a breakaway gap was created down under $49. After experiencing a continuation gap two weeks later, the stock continued to rally hard. From here we can see obvious divergence with the RSI, where the share price has gone to a new high, but the momentum was trending down. The stock has how gapped up once more to form an exhaustion gap, with a lot of volume coming in yesterday (circled). This means that after rallying 14% in two months, there are lot of investors out there suffering from a "fear of missing out". As a result, the price has taken a final run up towards the top. You only have to look at BHP's last move up to $50 last year to see a similar situation.
Therefore if you are holding the shares for a dividend next month, there is an opportunity to write a covered call here to pick up some more income. At the moment the $52.01 European August Call is selling for about $2. So once CBA goes ex dividend, if it has still fallen enought to be under $52.01 by expiry, you keep that $2. You therefore get the dividend (which last year was $1.88), plus another $2.