Wa alaykum salam wa rahmatuLlahi wa barakatuHu,
The walimah’s time starts at the marriage contract and extends until after the marriage is consummated. It is best for the walimah to take place after the marriage is consummated because this was the practice of the Prophet Muhammad (upon him be peace). (Mughni al-Muhtaj 4/406)
And Allah knows best.
Answered by: Shaykh Yaqub Abdurrahman