adding proteins to existing clusters

[nohayoussef]

Hi,
I have created clusters from blast output with a subset of proteins (all versus all blastp from ~800 genomes) that I am working with. Now I need to add more proteins (I expanded to ~2000 genomes including the original 800) to the existing clusters (plus of course add more clusters if needed) using new blast outputs. I have created 2 blast output: the ~1200 extra genomes proteins versus all the ~2000 genome proteins, as well as the ~800 original against the extra ~1200. The three blast outputs can of course be combined in one huge file and be formatted to the abc format. But my question is: can I keep adding to the original clustering file, or do I just need to start all over? Thanks for your time