The prescaler divides by 256, and TMR0 divides by 256.
So the overflows only happen every 65536 counts.

With a frequency of 301234, there will only be 4 overflows, with 39090 remaining.
That's 152 in TMR0, and 178 in the prescaler.

Another way to look at it is to convert the Frequency to a HEX number
#301234 = $4:98B2

Now it's easy to see that there will be 4 overflows, TMR0 will have $98 = 152, and the prescaler has $B2 = 178.

HTH