How long is permanent? Other than my time in the Army, my permanent positions have lasted from 2-4 years, and my contract gigs have lasted from 6 months - 4 years.

I now look at all positions as temporary and plan accordingly. If the position requires that I become an employee, then I have one "rate". If I'm paying my own benefits, then I have another "rate".

My only suggestion is, don't burn any bridges with the software vendor. If possible, new employer accepts, offer to still provide support with the software vendor on the side. Use vacation "hours" if necessary. That way, if the "permanent" position doesn't work out, you have a fallback position.

Good luck.