If a person is reassured about the beginning of the month through the astrologers, will his rulings be…

Answer

In the name of Allah, if the person is reassured, that if he swears by Abu Al-Fadl Al-Abbas (PBUH), he must follow whatever comes after it, because reassurance, absolute, and assertion are a proof against every sane person. As for what the astronomer says astronomy, even if the latter is right, it is not permissible to rely on him/ her.