I think she should talk to her diabetes team so they can help work out the dosages she needs - as mentioned in many places nobody is the same, so she may need a change in dosage - either the basal or the insulin/carb ratio.
Having just changed insulins I know the new dosages have been a bit of trial and error and many blood tests to work out what is right, as someone who has had diabetes for far too long I can work out what changes I need from testing and experience, but your sister will probably want to get advice form her team as she is new to insulin.