Or they could fly to Algeria, Morroco, Abu Dhabi even, then onward to whatever training they get, coming back the same way, on their own passport (or more likley a forged one), these are easy moves, especially if you are only a petty criminal, never even been in prison.
My point is/was that there are much less risky ways of "getting in" than the "hiding in refugee" boats.
I'm not saying it couldn't happen, but the time scale from October 3rd is too small, this had been planned for months, and judging from its clinical operation, there weren't late additions to the crew.
Only one of those targets on Friday were well known, and would be considered high profile, the others all soft, and easy, where maximum casualties would be gained before there could be any reaction, and I'm pretty sure they were carefully selected, and scouted, because of the very people who went there, ordinary every day folk, in ordinary local bars and cafe's, who are a better target to these terrorists, because of the terror factor. Even the football stadium plan, which sounds like it went wrong luckily, was going after ordinary every day folk, not high profile targets.