Conversation so far:
What rewards did Vasco da Gama receive?
Vasco da Gama received the town of Sines as a hereditary fief in December 1499
What happened with the town of Sines after Vasco da Gama received it as a hereditary fief?
Vasco da Gama receiving Sines turned out to be a complicated affair, for the town still belonged to the Order of Santiago.
What happened after Vasco da Gama received Sines the town that still belonged to the Order of Santiago?
the fact that Sines was awarded to Vasco da Gama by the king provoked Lencastre to refuse out of principle, lest it encourage the king to make other donations of the Order's properties.
What did Vasco da Gama do with Sines after provoked Lencastre to refuse out of principle lest it encourage the king to make other donations of the Order's properties?
Vasco da Gama would spend the next few years attempting to take hold of Sines, an effort that would estrange him from Lencastre

Question: What else was da Gama doing at this time?
Self-contained rewrite: What else was da Gama doing at this time aside from attempting to take hold of Sines, an effort that would estrange him from Lencastre?