Once mycelium reaches the casing top, DMR reports pinheads within 3 to 5 days and about a week more to full size. TNAU, working in Tamil Nadu, reports buttons about 10 days after casing and harvest 7 days later.
Both are published Indian figures. What matters is your own count. If expected development is absent, investigate strain and stage, colonisation, casing preparation and moisture, room conditions and crop health. Timing alone does not identify the cause.

