Comparing the fractional abundances for three constraining species, CH₃OCHO (top), HC₃N (middle), and C₂H₅CN (bottom), using different initial temperatures (10 K in magenta, 15 K in green, and 25 K in yellow) at a gas density of 10⁷ cm⁻³ for a fast warm-up. The vertical lines show the time corresponding to a temperature of 100 K for each initial temperature. The observed abundances (horizontal lines) for G35.20 A are shown for reference.