My investment journey: Power backup reality check

Did a site visit to Prestige City last weekend. I work in real estate, so I know builders ka marketing spin, but buying for myself is a different game. They're promising 100% power backup for flats, not just common areas. For an investor like me, consistent power backup is huge for tenant attraction and resale value, especially in Bengaluru where power cuts are common. I've seen projects jahaan initially they give full backup, but after a year, it's only common areas because of high maintenance costs ya builder back out ho jaata hai. Does anyone living there or who has invested in similar big projects like Prestige City actually get full flat backup long-term? Or is it just a temporary thing for initial sales? What's the ground reality for power backup in Bengaluru projects?