Nearly 11 week old waking more at night

[Samp79]

My lg is 11 weeks tomorrow and up until 4 nights ago was generally sleeping until 3 to 5am. Now it's 12.30 to 2 am and then up again between 3 and 4 am. Any suggestions. She is breastfed except 1 top up of expressed at 3pz and then formula 1 to 2 is if needed

I expect she goes back to sleep again after a little feed. She is still very young. Cuddle her in bed with you and she will feel snug and secure.