Offseason Workout vs Speed workout

hey guys whats up.

I have a question about my offseason workout.

Right now i have started my offseason workout for a week and i am doing heavy strength lifting. I was wondering when i should start doing speed workouts more.

Like boxjumps, burpees.

When should i start my speed and conditioning program. Should it be in the late preseason like 2 months before we play or what. Also if you do this and work on speed and conditioning won’t you lose the strength that you developed during the 6months in the early offseason. Just wondering.

I was thinking i am going to workout with heavy weights during august, september, october, november, december, january, february,

Then during march and april i will do speed exercises/ conditoning 4 times a week and only do heavy lifting 2 times a week just to maintain my strength. Does this sound good?