Battery replacement special = JOKE

Why should our iPhones be send in to head office to replace batteries (new discount to replace faulty bad product item)? IT WILL TAKE MINIMUM 10 DAYS???? Who earth has such a timeframe available without a phone, goodness. The technicians at iStore informed me that they have all the s****s and tools to conduct the service in-store! Why??? Apple is loosing its grip on customer experience and service!