Different treatment of contract customers on packages provided by MTN

I just learned that MTN retention department offers different contract bundles to customers who were on 2016 Black-Friday promotional contract bundles of 100GB and 500 minutes for R470, while their existing contract customers are offered meagre contract bundles of 20GB for similar price. It seems that MTN is taking likely existing customers who had been loyal customers for over 8 years. This is the same mistake ABSA bank lost customers by offering monthly account bundles to new customers vs old existing customers. Do not try and say it was a 2018 Black-Friday special as i have colleagues who have only been with MTN for about 3 years and upgraded weeks before this Black-Friday and on Monday (27/11/2018) past this weekend. This is totally unacceptable and exploitation of existing customers and preferential treatment given to certain contract customers.