it will never go out of bounds, the highest amount or lowest amount is not protected, so after 3.40282346638528860e+38 it will goto 1.40129846432481707e-45 resp, Float.MAX_VALUE Float.MIN_VALUE it's one nice big cirkel horray \o/
Actually it is quite likely that it will simply stop incrementing long before it gets near the max value.
Because the delta will be so small relative to the size of the time value that adding it won't even change the least significant bit so the time value remains the same before and after the addition. It's the nature of floating point values.
Try adding 1 to a number in a loop but only keeping 2 significant digits in the total... once you get to 100 you are stuck