How should lessons be adjusted when a university student with a busy week may want to change lesson duration after a few weeks?

Treat the first weeks as useful evidence. If attention remains strong and goals are consistently unfinished, longer may help; if quality falls well before the end, more time may not be the solution. When study time is limited, one precise practice task between lessons is more realistic than a long unspecific assignment. Progress is more meaningful when the learner can repeat the skill with less help over several lessons.