Yes. You set delivery times and shipping conditions for your sales account.
Company defaults live under preferences, then shipping & delivery. There you set a default shipping time as a min and max in working days, plus shipping conditions such as costs, free shipping, thresholds, and destination:
Working days exclude weekends and holidays. You can optionally override the delivery window on a listing with its own min and max working days. Without an override, the company default applies. Listings without a usable shipping time are not shown to buyers.
You can edit delivery times on listings in the portal, via import fields for min and max working days, and through listings write on the Supplier API: