Short answer
Choose cloth for the places and seasons where you expect to wear these dresses. Ask the tailor about fibre, weight, weave and care for the specific options; a city's name alone does not determine the right cloth.
Silk–wool crepe for structure, matte jersey for travel, seasonal silks for the occasions that justify them — linings and support chosen in the room.
September serves four-season commissions; late-October fittings look straight to winter — heavier flannels, a cashmere overcoat conversation, and cloth for the ball season that follows.
The full cloth books span fresh open weaves through four-season high-twist to winter flannels and cashmere blends. Bring the tailor your calendar; the shortlist comes back two or three cloths wide.
The itinerary is a proposal: months are planned, dates and venues confirmed individually. Final quotations are confirmed in writing before you commit.