IMO Callam is right :), while remembering what the definition of acceleration is.
I actually can feel myself slowing down around the 20-25 yard mark and the rest of the climb is not as quick. Should I limit my distance to what I can run feeling fast for now?
You may want to consider something like a bit of reduction, yes; most studies about some sort of resisted runs (effectively what a hill is) look to break down of form as being one indicator of what you do not want to happen (ground contact time, body position etc.), you may slow down but only within a “reasonable” percentage as another indicator and many of those same studies have limited distances of runs around 30m.