As done in previous IPCs, the competitors must submit the source code of their planners that will be run by the organizers on the actual competition domains/problems, unknown to the competitors until this time. The planners will remain public after the competition (here!). This way no fine-tuning of the planners will be possible.
(The following text was not changed after the competition took place, hence the future tense.)
In some cases, we will offer the opportunity to fix bugs that arise during the evaluation period, but any changes after the submission deadline will be strictly limited to bugfixes only. We will use a diff tool to check that patches don't contain new features or parameter tuning, and will reject patches that don't look like minimal changes to fix bugs. It is your responsibility to provide patches that are easy to verify with a diff tool. We reserve the right to reject changes for which the only-bugfixes rule is unnecessarily hard to check (e.g. because you reformatted the whole code).