Is it permissible for a wife to stipulate the postponement of wearing the niqab after marriage for a certain period, and is it permissible for the husband to agree to this condition?

You are advised to hasten to wear the niqab and not delay. Islamic countries have become an environment that embraces freedoms, and the niqab will not be an obstacle; rather, it will help in achieving success.

Delaying good deeds under the pretext of lacking sincere intention is a loss, for "abandoning a deed for the sake of people is hypocrisy." The fortunate believer is one who seizes opportunities for good and does not postpone them, because the heart is fickle and resolves weaken.

The niqab is obligatory according to the majority of scholars, and stipulating the postponement of an obligation is invalid. If the questioner follows those who consider it merely recommended, then she should ask them.