The work car R33s (not R33WFs) were based from the 36th-38th St. Yard after retirement, so it is safe to assume that the R32s are replacing the R33s (the R32s are assigned to 36th-38th too...); the R33s have no air conditioning while the R32s do, and the R33s are somewhat older...
For sure the R33WFs are not being replaced entirely by R32s...