When your contract ends
Helicopters, we are told by the rest of the world, are unsafe; it follows that our jobs are also unsafe. I worked for two major airlines who shouldn't have been in helicopters at all; when it all goes wrong you have to be long gone. If your contract has ended but you haven't yet found another job then you must take this lesson to heart.
Any helicopter pilot or engineer/mechanic MUST maintain an up to date jobs file containing a current CV (simple) together with an extensive list of employers and their Chief Pilots around the world for whom you are qualified to work. The more guys you know around the world the better.
At regular intervals, and while still in apparently safe employment, you should keep in touch with these contacts; either they will bin your request or demand you climb on the next aircraft. It's a lottery and not for the faint-hearted. Finally NEVER leave a job on bad terms.
If you want more job security go be a lawyer or a doctor.