Using the verb ‘stayed’ does tend to imply you slept there and were there ~24 hours. If you had ‘stayed two days’ or more, that really would imply N 24 hour cyc

Using the verb ‘stayed’ does tend to imply you slept there and were there ~24 hours. If you had ‘stayed two days’ or more, that really would imply N 24 hour cycles approximately, and at least N-1 cycles certainly; any other number besides 1 in your sentence would mess up your example. You already know the word “day” has multiple meanings, and in some contexts (such as time codes and dates and time measurements, using “day” always means 24 hours). An example using one of the meanings is irrelevant, it does not contradict the other meanings.