Hi Red
If in doubt change the fluid ASAP.
Brake fluid absorbs moisture from the air and as the water content in the fluid increases the boiling point of the fluid lowers and the other critical problem is that as it absorbs water it then allows corrosion to begin in brake lines, master cylinders, slave cylinders which will end up costing dollars to fix.
Fluid manufacturers advise fluid should be changed yearly or sooner if contaminated.
Dimi