Is one who follows legal dispensations out of ignorance of their ruling, or out of ignorance that his action constitutes apostasy, considered an apostate or a heretic, and is one who follows them in some matters a disbeliever?

Following dispensations are of two types: The first is fixed in the Shariah and it is legislated to adopt it. The second is following the fatwas of jurisprudential schools of thought (madhahib) that are based on ijtihad, merely to adopt what is easier without a Shariah-based preponderant opinion or imitating the most knowledgeable. This latter type is blameworthy and is not permissible in Shariah. Whoever does this is a disobedient Muslim (Muslim fasiq) and is not outside the fold of Islam.