ASReml that I use enable estimation of (also) phenotypic correlation with repeated records. A conference presentation "Using the animal model to estimate genetic parameters in plants" (downloadable from ResearchGate) provides some information - if that may possibly help you. Your statistician at CSWRI should be able to help you.  

Wombat is a good program!! I think that the reason is that you can estimate the Correlation of the Phenotypic values with knowledge of the other covariance matrix. I will send you a wonderfull paper from Dr L Schaeffer, which nicely covers this topic. and the other from Dr. J Van der Werff, both are nice and you will find to solve your problems in understanding RR.

You can find the correlations of the covariance (Genetic covariance function) by using

Gcorr=inv(sqrt(D)*H*inv(sqrt(D).

You can estimate several points in the RANGE of ages .... you can do the same for the Environmental covariance fuctiosns.....

I think that you can get P=G+R and proceed accordingly; or you can get that the covariance function of the phenotypic values is the sum of H+W.

I will check this ...... But look at the comment of Dr Schaeffer in relation to the values of the correlation matrix dependig upon the scale.

But you can always get from one scale to the othr as it is explicitely explain in DR Scaheffer notes.

The paper from Van der Werff if for the reason that he explaisn explicitely how to work with the covariance funcion.

Finally I will send to you a commented  text FILE, on Dr Scaheffer simple example!!! The code is for MATLAB, but you can addapt it for the SAS PROC IML. It is easy with MATLAB as compared to IML.

I hope this help you