Just know these are all opinions based on each parents own personal experience, as is my response. My son did not have interest from any schools at the D1 level until he attended a P5 camp and had a great performance while also living 90+ with every fastball, during fall of his senior year. But as Fenway pointed out, athletic scholarship money is going fast. Both P5 schools that my son was talking to either had or were not willing to provide athletic money. Those that met him late early in senior year called him a unicorn, because no one was familiar with him due to being a late bloomer like yourself.
I would second PABASEBALL's recommendation of sending emails out with heading that includes your velo. Put together a short video of you pitching and, if possible, include a radar gun with velo. I would also recommend a post to flatground.