For my kids, standardized testing was always targeted to be done before Senior year. But this can depend on a student’s progression through Algebra 2.
Requests were made for recommendation letters at the end of Junior year, but the background data and actually writing wasn’t until the Fall. Junior year was just getting the “will you write/yes I will” confirmation.
Campus visits were through the Spring and Summer.
Finances started with 529’s before the kids were born. Financial viability and constraints were always part of ongoing financial planning. The actual FAFSA/CSS was a fall task - not overly complicated, at least in my case.
Essays started after the school year with the Common App prompts, but the final release of school-specific questions on/around August 1 triggered most of that effort.
But I suspect my kids, and most on CC, plan much more in advance than the average US high school student. Starting all of these in the Fall of Senior year is probably still the norm.