3 to 6 months minimum. Sometimes 12 to 18 months. The lead time in broadcasting is incredibly long for various reasons:
1. Even after a carrier signes a programmer then advertising deals need to take place. Old deals need to be renegotiated in light of the new carriage deal and new deals for new advertisers take a while to get in place.
2. A carrier and programmer usually "test the waters" using Neilsen equipped homes or Arbitron polling for 1 to 4 months before going live in any significant fashion. This phase is where DD in broadcasters and programming REALLY PAYS OFF, because this is when you can "discover" these deals before the rest of the world does and profit from it.
3. Carriage companies and programmers then look at the results as they come in and then decide if tweaking needs to be done (based on poor to mediocre results) or a major push needs to me made to "get to market" as soon as possible.
4. Then they both PR a day or two before actual startup.
Steps 1 and 3 are a "closed loop" until all parties are happy, then step 4.
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