It'll pitch up ... assuming it's the wheels that hit the bump ...
There's two way to land these things ...
1) full stall, stick back, in which case the 'bump' of landing and any more bumps during roll out can't make it pitch up any more, or at least can't give it enough pitch up to fly ... most of my landings have a 'settling' time with the stick full back ... at least when I'm out of practice ...
2) wheel landing, in which case, the 'bump' of landing had better not really be a bump, and any reaction from the ground must be countered by a forward movement of the stick to counter any tendency to bounce and start flying again ...
Hope that helped ...
