I used to increase my basal a few days before period started and that was fine for me. As soon as my period started, I knew to reduce my basal back to normal.
Everyone is different. If your highs only occur after eating, perhaps you need to increase your bolus . . . Maybe even both basal and bolus!
After a few years, I found I no longer needed an increased basal, so things can certainly change
If you left a message for your nurse, hopefully she'll get back to you soon. I can't remember if I asked at the clinic, or just decided to make changes myself. (I was still on MDI in those days).