Why do we need to update the radio system? What will happen if we don't? These are valid questions. It's a pretty big expense, after all--probably more than an elementary school, but less than a middle school. Experience with prior radio systems, beginning in 1933 (see page 9) suggests that the life span is around 25 years, and the core of the current system dates to the late 1980's.
It is not like a carton of cottage cheese, however--it doesn't have an expiration date, and you probably won't open the lid tomorrow and be tipped off by a bad odor. The current system (EDACS) is no longer sold or manufactured, and support is ending soon. It might keep working just fine for quite some time, but with every passing week, we are increasingly susceptible to failures, and it will become more and more difficult to recover from those quickly.
Think of it as a 1989 Honda Accord. It's 25 years old, it has 272,313 miles on the odometer. It has had regular maintenance such as oil changes, tune ups, and filters. It has been in the shop twice for body work following fender-benders. It had a leaky head gasket replaced on warranty in 1992, a valve job sometime during the Clinton administration. It's had a new exhaust system, alternator, struts and shocks, ball joints, two timing belts, and few batteries as and several sets of tires over the past couple of decades. Thanks to regular wax jobs, a garage, and some seat covers from JC Whitney, it doesn't look bad at all. I't has been a reliable and economical car, and it still gets you to work every day.
From the time we get the green light to move a radio project forward, we could be a couple years from flipping the switch. It will take a few months to develop the specifications and draft the request for proposals, a few months to solicit and evaluate responses from vendors, a couple of months to develop and get approval for a contract, several months to design and engineer the system, a few months to install the infrastructure, a couple months to train personnel and execute the transition. If we got cracking now, we might have this all accomplished by 2017...or so.