Stock price when the opinion was issued
In addition to the 200-day MA, he looks at peaks and troughs. Look at the last low and the last high. The next high hit the previous high, so that's two relatively similar peaks. The stock may be below the 200-day MA (1st rule to sell), but it hasn't dropped below the last trough (2nd rule to sell). As long as it holds above the last trough, you're safe.
Don't go into full panic right now. Hold for now; if it breaks that second rule, then get out.
Sell Costco to buy DLTR? Costco is very well run, but their challenge is always growth. And their forward PE is 35x, which is high. Whereas DLTR trades at 17x, driven by growth and expansion. Long-term, DLTR has earnings growth and multiple expansion and a better total return over 5-7 years than Costco.