Is there a way to assess proportional hazards with the tt() function in the survival package currently?

I know that in the survival package, you are able to define a function which allows you to transform time in the event that you have a covariate that violates proportional hazards.

However, in the documentation I've seen, you should be able to run a proportional hazards test using cox.zph, but each time I try to run it, it says that the "function is not defined for models with tt() terms."

Is this a change that occurred recently, or am I implementing this incorrectly? The code is below.

cox0 <- coxph(Surv(time=st.time, time2=end.time, event) ~ black + tt(black) + christian + 
                cluster(id), data =df,
              tt = function(x, t, ...) {
                mtrx <- model.matrix(~x)[,-1]
                mtrx * log(t)
              })

test <- cox.zph(cox0, 
                transform=function(t)log(t))