Agreed. 5x5 early could be done, but not to anything close to max loads. I like to use the higher rep ranges to prepare the muscles and tendons for the higher weights in weeks to come. I think of it as more a transition.
An example for a HS athlete who is sub 11 was:
wk 1 3x10
wk 2: 4x8
wk 3: 4x6
wk 4 5x5 moderate
wk 5 5x5 heavier
The 5x5 heavier sets were essentially 4 warm-up sets and 1 max effort set. This lasted for about 6-8 weeks, before I moved to a more “wave-loading” approach using 5x5, then intensifying as 3x3 towards the end of SPP.
All work will and can be modified based on the sprint workout itself.