Add timestamp to repeating task when marked DONE

Question

Say I have this task:

* TODO Task
  SCHEDULED: <2019-12-21 Sat 13:00 +1w>

and I mark it done the day after. Then, the timestamp becomes <2019-12-28 Sat +1w> and I lose the previous entry, ie when looking at the agenda on Dec 20th, I will not see the task. Even with log-mode on, I will not see it on Dec 20th, but on Dec 21st (the day I marked it DONE).

In the manual for Repeated tasks, it says:

As a consequence of shifting the base date, this entry will no longer be visible in the agenda when checking past dates, but all future instances will be visible.

Is there a way to get around this? Maybe an active timestamp of the current timestamp could be added automatically when marked DONE and the date is shifted into the future. Something like this:

* TODO Task
  <2019-11-30 Sat 13:00>
  <2019-12-07 Sat 13:00>
  <2019-12-14 Sat 13:00>
  SCHEDULED: <2019-12-21 Sat 13:00 +1w>

Answer 1

If you mark something done the day after, you could instead mark it done with org-todo-yesterday or org-agenda-todo-yesterday which will give it the correct timestamp.

Or, when you mark it done, add a note with the timestamp you want in the note. See org-log-done or (setq org-log-done 'note).