For as long as I have lived in Victoria BC (29 years) the utility has permitted contractors to make a temporary connection when upgrading or replacing a Domestic Service. For all intents and purposes a 120/240 volt max 200 amp 1 phase service. This meant the electrical contractor could cut the old consumer's conductors (not the utility drop) at the weather head and do the work then reconnect and apply a tag to the meter giving the meter info, reading, contractors info, and permit number. The utility would return and change the drop if an upgrade or make permanent splices.
About a year ago the rules changed and the utility now requires a "Work With" IE the utility comes and cuts the service in the morning and returns later in the day to re-connect. Now a contractor needs an appointment, and has to change the service within 4 or 5 hours or the customer goes without power until the next day or Monday if on a Friday. Of course this only applies where the new service has to be in the same location as the one it replaces.

How about where you live? What procedures are required where you work? All jurisdictions please.