I build a simple circuit with SN74AUC1G08 IBIS mode, just as bellowed. The simulation soft is Hyperlynx.
The waveform at R4(Blue) and R5(purple) is captured as followed.
The signal by simulation has a back hook when it reached the high level. So, I think the IBIS mode of SN74LVC1G08 is incorrect.
I build another simple circuit with SN74LVC00 IBIS mode, just like above. And I get the simulation waveform. These simulation results are correct.