My take:
Days of visit as listed in ads vary, but...
Typical 3 day visit for many providers: ...arrive day one at noon or later...so, mostly available only for evening appointments.
day two: good all day and nighttime.
day three: checkout at noon, or earlier... availability, if any, is limited to morning.
Provides a very short option for anyone who is not free at night.
And, it can vary, so one has to ask just when a provider is actually available on days 1 and 3.
(I've found it rare that a provider arrives prior to day one, or stays all day on day 3.