Short answer
Your written quotation confirms the delivery schedule for this dresses commission, including cloth, production and destination. Toronto's proposed visit window is MAY · JUN · SEP; dates and venues are confirmed individually.
For an event date, your written quotation confirms the schedule for cloth, production and delivery before you order.
Toronto's window
The proposed MAY · JUN · SEP visit is the planning point for Toronto commissions. Dates, venues and available appointments are confirmed individually in writing as the month approaches.
The itinerary is a proposal: months are planned, dates and venues confirmed individually. Final quotations are confirmed in writing before you commit.