Sleep regression

E
My LO had been steadily sleeping since birth, 4hrs at a time at night (9,1,430). Within the last week &1/2, he has decided to wake up every 3 if not every other hour (8,11,230/330) and of course I return to work next week. I just upped his bottle amount to 5oz in hopes of that solving it but haven't seen much change. Thoughts? Suggestions??