Depending on the type of sign you’re getting as well as what the local permit requirements and processes are are the largest factors in determining timeframe. On average for a set of channel letters to be permitted, fabricated and installed is around 4-6 weeks. Some city’s take only a few days to review and issue sign permits whereas others take upwards of 3-5 weeks (City of Omaha). In many scenarios we can have signage fabricated before the city issues permits but it's crucial that due diligence is taken initially to make sure a sign is able to get a permit before it's fabricated.
Projects that don’t require a permit can have turnaround within a few days to a week or two depending on scope of work and quantity.
Other factors that affect timing are weather and construction progress. When will your building be ready for signage as well as coordinating other contractors so we aren’t in each other’s ways. For the most part we work in all the different midwest elements however wind and lightning will get us grounded quick.  We don’t want anyone risking getting shocked and signs are giant kites which are safety concerns to people, buildings and structures etc. Some risks just aren’t worth being taken when a day or two can be precautionary.