"Lep pozdrav" is formal and used to greet public or use it in letters / e-mails. "Lep pozdrav" has similar role to "greetings" in English. You can greet someone at start or end of conversation. It means you acknowledge listener. Additional information: Note that the short version of it: "Zdravo" is always used as greeting at start of conversation and is more casual. There are other casual words who are more popular to use as "Hello" for example "Živjo".

Pozdravljena, yes that is correct, you can used it as formal or informal greeting, in the beggining or in the end, but it is more used in writing or on the radio. Lep pozdrav, x