Say a post reads "Live from Place A on the 24th*". That little star is not decoration. It tells you there is a matching mark further down the text, usually at the start of a short note, and that note belongs to the line you just read. The main line gives the headline version of the news, and the footnote gives the exception. We treat the two as one sentence split in half, and we never use the top line alone to plan anything.
A common exception is a broadcast schedule. The footnote might say that in some territories the broadcast is scheduled later, so that it fits local time zones. That means a date with an asterisk is not the same as a date for everyone. Some viewers get the date in the headline, and others get a different one. If the footnote does not name your territory, do not assume which side of the exception you are on. Open the ticketing or screening page the post links to and look for your own location there, because that page is where the real answer for you tends to live.
Time zones are the other quiet trap. A date in a post is normally the date at the place of the event or the broadcaster, not necessarily where you live. Because of the offset, the same moment can land on the day before or the day after for you, so the 24th in the headline might be the 23rd or the 25th on your calendar. Convert the time first, then decide whether the footnote changes anything on top of that. Doing it in that order keeps the two effects from getting tangled.
The footnote is easy to miss because of where it sits. It is usually at the bottom of the text block, sometimes after the links and before the hashtags, so a quick scroll can skip it. Look for a dagger or a double asterisk too, since those marks work the same way and point to their own matching note. A few honest limits: a footnote rarely lists every case, the wording differs from post to post, and the post itself may not say which territories are affected. When that happens, the linked page or the official account is the place to confirm.