My wife has 3 Terry bikes. The closest one to what you are looking at is another Isis. My wife's is conventional with the 650x28C tires front and back. It measures 50 CTC seat tube. My wife is 5'4".



My wife's other Terry road bike is a Symmetry from around 89 with the same geometry and seat tube measurement.



Her other Terry is a Jacarada MTB, seat tube 48 CTC.



Based on the picture of the Green Isis from the OP, it looks even smaller than any of my wife's. I'd think it will probably fit.
My wife didn't really like the small front wheel look, but it will obviously help fit smaller women.
Good luck!