Starting a DMA Pixel Buffer transfer and then?

After I start a pixel buffer transfer by binding to the unpack buffer, accessing the pixels, unbinding and starting a texSubImage2d transfer, I know I need to ‘leave it alone’ for a while to allow the DMA to take place, but can I send any OpenGL commands to happen after the transfer?

If I don’t flush or finish, will the commands just sit in line waiting to act when the pixel transfer has finished (or the queue is flushed)?