Even though Standard Time has existed since the mid- to late-1800's, some people still insist on ignoring its practicality. Railroads were the largest proponents, and first adopters, of the Standard time system. It made sense from a traveling perspective. Apparently people continue to use their own local "sun time" to make trips to the pharmacy.
Oxford Dictionary's Definitions (and the ones upon which most people agree.)
Morning: "The period of time between midnight and noon, especially sunrise to noon."
Afternoon: "The time from noon or lunchtime to evening."
Evening: "The period of time at the end of the day, usually from about 6pm to bedtime."
Night: The period from sunset to sunrise in each 24 hours."
Surely Understanding Nothing: I am calling in my refill.
CP: Jolly good. We serve to live.
SUN: I will pick it up later today.
CP: Lovely. Do you know an approximate time so I may prioritise it accordingly?
SUN: I will be in tonight.
CP: Thank you. As it is currently 2:13pm, we shall expect your arrival after 4pm.
SUN: What? No! I was thinking around 3:00pm.
CP: That's less than an hour from now. In no part of the world is 3pm considered "evening". I should have told you after 6pm as that is more in line with the true definition (see above).
SUN: Well I'll be there at 3pm.
CP: Next time, just tell me 3pm.
As a result of this conversation, we have instituted a policy in my pharmacy where all wait times are confirmed twice. First, we will ask if the patient is using EST, CST, MST, PST, ACST, (du) HAST, ORAT, or GMT. Then we must verify that a 20-minute wait in Standard Time is not expected to be ready next Friday, or in 7 minutes.
Maybe we should do the whole "synching of our timepieces" before patients leave the counter or we hang up with them.