when you blind scan that will happen...couple reasons
-sensitivity of tuner in receiver
-the LNB and its drift
as long as the frequency isnt off by more than + - 3 you should be fine.
I know when I blind scan 99W World Harvest will log as one of these 3 frequencies
4000
4001
4002
and a symbol rate of
26398
through
26402
so a mix and match....its normal. Commercial equipment usually it has to be nuts on to work but consumer has a little more "play"...no worries
The lower the symbol rate the more it needs to be spot on frequency wise