I have exactly 4 files - no new files.
At the end of the D/W/M/Y, I just add a new section on top and plan the period there. So each file has a record of all previous period plans. These are all cumulative files - I never clear out previous period's plans, just add a new section on top.
To see a task that's delayed multiple times, I just have to scroll down and look for [PARTIAL]/[SKIPPED] markers and their analyses. Usually, the daily analysis results in some corrective action that may also go into the weekly or monthly plans.
I'm going to run with this & iterate over the next few weeks. Last couple of days have already been nice, dumping all my disparate lists into these 4 files.
Do you just know it from daily analysis, or are you creating a new file for each day/week/month, and periodically look through those?
And how about weeks, new file for each week? or just clear it out every new week, and bring stuff back up to the year file?