Do we even have any reliable information on the whole Mt Gox distribution thing?
Some media are reporting that the actual number of bitcoins is not clear and can be anything from 65,000 to 140,000:
https://finance.yahoo.com/news/mt-gox-finally-repaying-customers-155925395.html

And, whatever the number is, I don't expect it will be distributed all at once, so it could start from July, but could span over many months (if not years).

But somehow I'm not worried too much about that, I don't think it has any potential of crashing the market, I think we could expect a few percent drop at the worst.