I started diving a rebreather in 2007 with about 400 dives logged at that time. I'd been shooting with a DSLR for about 3-4 years at that point. I've done another 400 dives on the rebreather since. I took my rebreather training course (Sport KISS mCCR) over a week long dive trip in Hornby Island BC. The certification requires about 12 hours or so of in the water instruction. By the end of the course I was comfortable enough to pick up my camera and add that to the mix. I considered this to be an important step of the instruction and training because I don't ever plan to dive without the camera. You also want to get a feeling for your trim and balance with the new gear.
I opted for a mCCR unit as well, because this REQUIRES that you pay attention to your pO2 readouts. It is supposedly easier to get distracted and not monitor a eCCR unit which most of the time can be expected to keep your gasses in balance. That is until it craps out and kills you if you don't monitor it. With a mCCR that is not an option and the training is all about developing the habits and practice of monitoring your gauges frequently and being extra careful on ascents.
My suggestion is to follow your comfort level. If you are not task loaded dealing with your dive equipment you can start to shoot again.
Final word of caution - if you are the sort of UW photographer that zones out and can't keep in sync with a buddy or other people don't get a rebreather. You need to be able to split your focus and remember that your safety and surroundings are job #1, and capturing the action is definitely a secondary benefit.