Short answer
Your written quotation confirms the delivery schedule for this shirts commission, including cloth, production and destination. London's proposed visit window is DEC; dates and venues are confirmed individually.
Your written quotation confirms the schedule and remote-order arrangements for your cloth and destination before you order.
London's window
The proposed DEC visit is the planning point for London 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.