One way to solve your problem would be to use loc 0 in the serial eeprom as a pointer. Store a 1 there by artificial means. Now store your counts in slots 1,2 and 3 (pointed to by slot 0) When the count reach 100.000 hex (yes live a little dangerously) add 3 to slot 0, this will now make you count to slots 4, 5 and 6.
The count will be: the value stored in the 3 slots pointed to by slot 0 PLUS ((slot 0 value)-1)*1048576. this will give you an eeprom that can count to (((eeprom bytes)-2)/3)*1.048.576
Have fun,
Erik