"Dublin" to a degree is not really relevent in this case as this thread and most of the posts are thinking purely about returns directly to France.
"Dublin" was meant to return the person to the country "responsible for their claim", which in the majority of those on the French coast, is likely to be Italy, Greece or other eastern European states.
Even then you have the issue of documenting the person and proving that they were actually in that country.
Add in the fact that has been repeated, but many still don't grasp, that the UN Convention does not require them to make a claim in the "first safe country".
Also with the whole process, times to obtain information , fully consider cases, deal with multiple appeals and challenges and then of course asking someone very very nicely to ...please show up for your flight back to Greece/Italy....when they have risked all in a dinghy to get here!
Yesterday was a real tragedy, but....trying to take something out of such a nightmare ...it has focussed minds, got people thinking, brought people to actaully talk to each other and hopefully bring about new ways of thinking and working.