honestly it depends on how much u trust the tranny and shop/yourself. depending on who is doing it. I had a new tranny install in mine at about 40k, its now 145k I dont have any maintenance records that says its been changed every 30K-ish. so its a bit of a gamble. looking at the color on the dipstick and the way the car shifts into gear (automatic btw) I say its safe and I would get one done now then maybe again in like 15-20k (advice from a friend, open to comments on that bit) then start the 30k intervals.
Toyota/Lexus transmissions, skip the additives, just straight TOYOTA TYPE T-IV.
Now in my case I do have a question to the mass: ~100K on automatic transmission, dipstick color still pink/red, TO FLUSH or Drain/FILL, by dealer?? That is the question.