Assuming that the agreement does not state when compensation has to be paid, section 47 of the Contracts Act 1950 applies.

Section 47 states that "Where, by the contract, a promisor is to perform his promise without application by the promisee, and no time for performance is specified, the engagement must be performed within a reasonable time. Explanation--The question 'what is a reasonable time' is, in each particular case, a question of fact."

In other words, the developer has to pay compensation within a reasonable time. What constitutes 'reasonable time' may differ from one case to another, depending on the facts and circumstances of the case.

For your peace of mind, it's better to appoint a lawyer and get their advise. Good luck!