The annealing behaviour of vacancy- and anti site-related defects in electron-irradiated p-type 4H-SiC was studied using electron paramagnetic resonance (EPR). We report the observation of the P6/P7 centers, which have been recently attributed to the C-Si-V-C pairs in 6H-SiC. The transformation of the neutral silicon vacancy (V-Si(0)) into the C-Si-V-C pairs is observed at the temperature range 600-750 Cdegrees. The EPR spectra of the positively charged carbon vacancy (V-C(+)) and silicon antisite (Si-C(+)) with their clear ligand hyperfine structures were observed after a 1350 degreesC anneal. Their central lines significantly decrease but can be detected after annealing at 1600 degreesC. The carbon vacancy is found to be stable at much higher temperatures than previously reported, even in irradiated material.