A form EFFECT is only publicly disclosed around 6:00AM ET, even if the company received the EFFECT in the middle of the day. This means it's possible for a S-3 or S-1 to have received EFFECT without the public knowing. For example, if EFFECT was received at 1pm today, the public wouldn't know until 6:00am the next day.

If a S-1MEF or S-3MEF is filed at anytime to add more raisable capacity to the filing, it is also confirmation that the company has received EFFECT because those can only be filed after the registration has received EFFECT.