Ehhh 6 hari berturut-turut tu memang unusual jugak lah, normally OPK surge tu 1-2 hari je, so I'd suggest check with your doctor to rule out anything like PCOS or hormone imbalance yang boleh extend the surge. Tapi yes, technically you can still BD during that window sebab sperm boleh survive, tapi the best fertile window is usually the surge day dan hari lepas tu (when hCG peaks), so maybe fokus BD during those prime days je untuk maximize chances. A few of us TTC mums dalam group chat memang pernah experience weird OPK patterns, and most of us ended up chatting with our gynae to understand what's happening, definitely worth a chat dengan doctor to get clarity on your cycle!