solarcatthree

Writing two or more copies of the data to an EPROM won't do any harm. At worst, you'll spend an extra minute or two writing data that never gets used. If the hardware they are going to be used in was designed for smaller EPROMS and doesn't properly drive address lines it wasn't expecting to see, then the extra copies become essential as you have no control over which copy of the data will be used on any given access, so all the copies must be identical.