The transport properties of single crystals of α-(BEDT-TTF)2I3 were investigated during the structural phase transformation to the organic superconductor αt-(BEDT-TTF)2I3 by measuring the temperature dependence of the conductivity, the thermopower and the spin susceptibility and by varying the annealing times (at 350 K) of the samples. Already after short annealing times above 60 K a hysteresis in the transport properties — depending on the direction of the temperature cycle — is observed, which does not exist in the original crystals. Possible structural differences between crystals of αt-BEDT-TTF)2I3 (with a stable superconducting state at 8K) and ßH-(BEDT-TTF)2I3 (with a metastable superconducting state at 8 K) are discussed.