I was guessing at the 11:20 as a frosh. I know I didn't go under 11 the one time (I think) I ran it, though.
My big jump was between soph year track and junior year cross country. I focused late on the 800m because I was needed on some late season relays, it was where I could run counties/regionals/sectionals since we already had few sub 4:30/10:00 upperclassmen so I didn't crack our championship season 1600/3200 spots. But looking back I probably could've gone sub 4:40/10:15 or so as a soph if I did those races late so the progressions from soph to junior track probably could've/should've been less dramatic. Still...I went from 4th or 5th guy on my team in XC and a useful 4x800 sub or 4th leg to 2nd team All State in XC Jr. Year so it was a pretty significant improvement.
For me, seeing how the upperclassmen went about their business (we had a D1 and a D2 guy from that class 2 above me), doing more quality miles versus just going out and goofing around for 5-6 miles a day and gaining confidence really helped me. I went to cross country camp that summer and went from about 5'4 to 5'7 or so that fall and was filling out. So I think physical and mental maturity were really my big changes.
After that breakthrough, my progressions were probably more normal.
My progressions are/were probably somewhat extreme, but I showed you them to prove that you may not be as limited to what the "normal" progressions are.
If you had told me soph year, I'd have run D1, I would've laughed at you. By Junior year mid cross country season, I expected it and focused on it.