2012 Cadillac SRX - Charging saga

One week ago my alert went off, Battery Charging System required service. I immediately pull up the info. Battery down to 11 volts, took to dealership. wow 191$ an hour labor two months ago was $135 …already put on new battery, they did the alternator. Still doing the same. Did find out that the alternator you need depends on whether or not was made before or after 1/12/2012. Mine made in Mexico 12/1/2011. Have seen many other complaints elsewhere about this non fixable voltage issue. Would be curious to know if it is all the ones made before 1/12/2012 and if they changed the alternator type for this very reason during manufacture to avoid having enough of them out there to have a recall. Then they tell me the same tire that was replaced 3 months ago needs replacing, they just fixed recalled toe in same day for same tire. I am finding through research this is a common electrical issue that’s not being reported. They were supposed to run a check on the Battery Charging system when they completed the alternator install. However they either did it and it failed and they didn’t want to say so or they didn’t do it at all because they knew it would fail and that’s why they didn’t charge me for it. At any rate over GM products obvious bad engineering in my opinion.