Good question! First, I would speak with (the project developer / person who will accept requests for traction) to find out what his preferences are. Believe me, you want to make life easier for the support person and make sure that you are doing the “Right Thing”. Creating a traction request workflow that is convenient for him will be long.
OK, that said the nature of the changes (and pull requests) that you make? Are they “named functions” or are they “small” bug fixes?
Also, is there a significant overlap in the lines you touch (so that merge conflicts between pull requests can occur) or are they mostly orthogonal?
If they are "named functions", with little overlap / merge conflicts, I would bind one new named branch for each function. If they overlap and / or are tiny bug fixes, I would probably go with “constant pull requests from the same forked branch” if it's OK with the maintainer.
You may know this, but I put it in posterity; git branches are cheap, cheap, cheap. If in doubt, create a new branch.
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