Inconsistency between guides

Bah, I've quite simply been trying to get info on mission bits and missions themselves because nowhere does it say, on any site or guide I've looked at, specifically what the highest resource ID of a mission can be.

As for mission bits, one guide for EV and EVO says that they can go from 0-511, another says that there's only 255. What's true, here?

Mission bits are 0-255 in Escape Velocity , 0-511 in EV Override. Mission IDs are 128-383 and 128-639 respectively.

Even though it wasn't nearly as major an upgrade as for EV Nova , Override did add a few features and increase a number of maximums.

The 255 in EV was remarkably restrictive - it was definitely a very welcome change adding the extras in EVO.