What is happening in this area post stitch abscess breast reduction?

Thank you for your question and photos. It is difficult to give you an informed opinion on this problem without examining you in person. I would recommend keeping your scheduled follow up appointment with your surgeon. Best of luck. 

Dear Smallerandtaller,I understand your concern. However, without a proper assessment it would be difficult to determine what is wrong. It is best that you visit your plastic surgeon for further assessment. Only after thorough examination you can get proper recommendations and advice. Daniel Barrett, MD, MHA, MS 
Certified, American Board of Plastic Surgery  
Member, Am. Society of Plastic Surgery

Things will improve a lot over the coming months and this will not be the final result. This is not unusual  and it will take 6-12 months for you to be able to assess the final result. Everything now looks well healed and you should ask you PS about scar management and massage.

The photos do not lend themselves to much insight except to say it looks like a nice outcome otherwise and will probably resolve to your satisfaction given some time.   Continue to follow up with your doctor.   Good Luck!