Can I flip my worn chain to extend it's life?
I would say that this won't have any effect.

Flipping the chainring on a single speed makes sense as you use the other side of the teeth on the chainring which have not been used before. But with the chain it's a different story: The stretch is independent of directions so reversing its direction won't change anything. Also on the small "rolls" in the chain links on which the chain lies on the chainring I wouldn't expect any effect as they aren't fixed in the links but can rotate and therefore should wear out equally all around their circumference.