My first fruit beer... I have just racked a wheat beer base onto a secondary of food blended frozen cherries. Am I ok to give this a bit of a stir now and again? Im aware introducing too much oxygen is bad, but I just can't see how the cherry paste locked at the bottom of the tub can impart any flavour into the liquid if it is not touching the beer.
Give it a swirl. I would avoid stirring personally due to potential sanitation issues.
As for potential oxidation, you should be good there. You just racked beer on top of the cherries, so there's going to be some additional fermentation of the sugar from the fruit. This should produce enough CO2 to clear out the head space in your carboy, so you shouldn't have any oxygen left in there to worry about.