In the following document
http://www.kodak.com/global/en/professional/support/techPubs/j86/j86.pdf
Pages 1-8 pertain to Kodak T-Max RS Developer.
Pages 9-12 cover Kodak T-Max Professional Developer.
So far as I can see Kodak T-Max Professional Developer isnt intended for replenishment. Its unlikely that youve hurt your film by doing so with the same developer concentrate, but it really isnt recommended by Kodak.
It might be that if you continue to replenish the same original batch, the reaction products might eventually become concentrated enough to cause problems, but I dont know. There must be some reason that the Kodak data doesnt recommend this.
Kodak T-Max Professional Developer has a stated capacity of 48 rolls or 3840 square inches of film per gallon at working strength. This capacity is obtained by reusing the developer according to the following schedule for hand tank use (note the warning about push processing):
Develop the first 1/3 of capacity at normal time N for the particular film and temperature in the chart given in the above document.
Develop the second 1/3 of capacity at N + 1 minute.
Develop the last 1/3 of capacity at N + 2 minutes and then discard the exhausted developer.
For example, to develop 6 rolls of 135-36 T-Max 100 film in a Jobo 1520 2-reel drum (stated inversion volume 485ml) at 20C wed develop
Rolls 1 and 2 at 8 minutes
Rolls 3 and 4 at 9 minutes
Rolls 5 and 6 at 10 minutes and discard the exhausted developer.
Note: 6 rolls require 473ml of working strength developer, but we need 485ml to satisfy the volume requirements of the Jobo 1520 tank.