Can formula supplementation in first 48 hours cause issues for the baby later in life? i have seen some theories talking about changes to the gut biome. will this correct as the baby is moved primarily to breast milk? what other issues?

Formula use was once the standard infant feed for generations of infants after staph infections were common in nurseries. Breast feeding was considered a point of origin. Babies were bathed in antiseptics, wrapped in sterile blankets & moms told not to unwrap them for feeds. Infection control improved & we are back to natural feeds. Today babies do well either way. It is not a health issue.