Continued redness under breasts, could it be an allergic reaction to the sutures? 6 weeks post BL with augmentation. (Photo)

I am sorry to hear about the difficulty you have had, especially communicating with your plastic surgeon.  I think that you are wise in continuing to seek follow up with a board certified plastic surgeon in your area. Hopefully, your primary care or OB/GYN may be helpful in finding you this referral. Generally speaking, redness on the lower aspects of the breasts after breast reduction or lifting can be seen occasionally; this redness is not necessarily secondary to an infection. The differential diagnoses may include: venous congestion (blood flow related skin changes) or hypersensitivity. Again, best to seek in person clinical evaluation. Information provided in this response can only be meant to be general and not specific to your case. Best wishes.  

Thank you very much for sharing your concerns with us.Its too early to talk about final results with only 6 weeks post op.To avoid postoperative swelling and pain after performing a Breast augmentation with lift procedure, I recommend to my patients, to limit the arms movement for two weeks, also it's not advisable to carry weight.Finally, I recommend you always use a therapeutic bra.Respectfully,Dr. Emmanuel Mallol Cotes.-

If all your bloodwork seems fine, no signs/symptoms of an infection and all you have is redness, then it is unlikely an infection.  Could be a prolonged redness just due to the stress the tissues are/were under.  Your photos look fine, I don't see anything to worry about.