What is the ruling on delaying the fulfillment of a vow when one is unable to do so, and is it permissible to pay a financial vow in installments in this case?

If the vow is time-bound (mu'aqqat bi ajal) and the one who made the vow (al-nadhir) acquires some money when the term is due, he should give in charity (tasaddaqa) what he can afford and expiate (yukaffir) for the remainder with an oath expiation (kaffarat yamin) due to his inability to fulfill it. However, if the vow is absolute (mutlaq), then if he intended to spend it all at once, he should wait until he acquires the full amount. But if he intended to distribute it and obtained some of it, he should give in charity what he can afford, and the remainder stays as a debt upon him (fi dhimatihi) to be given in charity whenever he is able.