How long can a seller take before responding to my offer?

There is a portion of the Agreement of Purchase and Sale called the “irrevocable”, where the Buyer places a date and time that their offer is valid until. During this time, the Buyer can not revoke the offer they have submitted, and Seller has the ability to accept, sign back, or decline the offer. This irrevocable period is determined by the Buyer and their Realtor with strategic significance, and can be allotted for any amount of time. In competitive situations, Buyers tend to choose shorter irrevocable periods in an attempt to avoid further competition with others. There could be situations where a Buyer is offering on a property where there are multiple parties involved as Sellers, such as an estate sale, and it is not uncommon for 24h or 48h to be requested as an irrevocable to ensure all selling parties are able to be contacted to go over the offer.