Brief Answer:
You can switch to cow milk with added supplements

Detailed Answer:
Hi

Thanks for asking on this platform

After 2 years of age one can use cow milk with supplement like Pediasure/Junior horlicks.
The formula milk is mainly made for infants where mother's feed is not available due to any reason, as cow milk should not be given below one year.
Even after one year formula milk can be given because these formulas have added supplements needed for growth. Most of the supplements like Junior horlicks or Pediasure can be given after 2 years of age.
So after two years of age cow milk with added supplement is my suggestion for almost all unless there is some allergy to cow milk(very rare). The company claims that this nan pro 4 can be given upto 24-30 months and some special nan 4(optipro) can be given upto 4 year.

I hope this helps.
Please let me know if you have any more questions.
Regards

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