Fewer than 24 hours vs Less than 24 hours

Some examples from the web:

• We then went to another much larger list, made another announcement and another again all the seats were taken in fewer than 24 hours. Ok so big deal.
• The Number Of Dead Pigs Found In Shanghai River Doubles In Fewer Than 24 Hours. Dina Spector. Mar. 12, 2013, 4:52 PM; 15,599; 20 · facebook · linkedin ...
• The client has spent fewer than 24 hours after presenting in the ER without being placed in observation status. •. The client has spent fewer than 48 hours in ...
• Applicants under 21 years of age who are not active-duty military and have fewer than 24 hours of letter-graded college credits must follow the University of ...

Some examples from the web:

• Less than 24 hours away are the grim theaters of war.
• Means this man was in space Less than 24 hours ago.
• Where he was killed less than 24 hours later.
• ZOE: It's been less than 24 hours.
• Less than 24 hours to go before the Iowa caucuses, the Republicans have a broad field with no clear front-runner.
• CABE: Doctors said she has - less than 24 hours.
• Less than 24 hours' notice.
• Less than 24 hours later, Google shipped an update fixing the holes.
• Less than 24 hours notice no refund available (sorry).
• Less than 24 hours 'til the next fight.
• Less than 24 hours before cyrus petrillo confessed.
• Less than 24 hours later, it made another landfall on the island of St. Croix, with the same intensity.
• Less than 24 hours: one night charge. No cancellation at all: total amount.
• Less than 24 hours after publication, a video interview with Abu Thurayya filmed two days before his killing had already been viewed 31,000 times and shared over 72,000 times.
• Less than 24 hours after we interviewed Benji Dunn about Ethan Hunt He was on a plane to Vienna with tickets to the opera.
• Cancellations: Less than 24 hours total amount first night
• Less than 24 hours 100%of total price charge
• B. Less than 24 hours of cancellation incurs a cost of one nights stay.
• Less than 24 hours prior to arrival or cancellation without prior notice no-show: 100% of the total balance due will be charged.
• Less than 24 hours notice of cancellation will result in guests paying the full amount to the hostel.