I thought the plan was to have no gaps at Mary's place -- he'd travel back for that in any case to get back there/then.
I am not sure, I remember having the impression that Harry was making specific time travel plans in response to meeting the patronus. They had already travelled backwards in time, I am not sure how much time has passed. I will re-read the chapter later tonight.
Though if it was non paradox causing either way, then the patronus was acting in accordance with another global law of the HP:MOR universe: it was more awesome for the patronus to meet Harry in Azkaban and make the situation more complicated.
- This thread has run its course. You will find newer threads in the discussion section.
Another discussion thread - the fourth - has reached the (arbitrary?) 500 comments threshold, so it's time for a new thread for Eliezer Yudkowsky's widely-praised Harry Potter fanfic.
Most of the paratext and fan-made resources are listed on Mr. LessWrong's author page. There is also AdeleneDawner's collection of most of the previously-published Author's Notes.
Older threads: one, two, three, four. By tag.
Newer threads are in the Discussion section, starting from Part 6.
Spoiler policy as suggested by Unnamed and approved by Eliezer, me, and at least three other upmodders:
It would also be quite sensible and welcome to continue the practice of declaring at the top of your post which chapters you are about to discuss, especially for newly-published ones, so that people who haven't yet seen them can stop reading in time.