Right. Excellent news for you. Don't miss this opportunity!
Treatment or trying to deal with retinopathy is an in depth issue and I won't go in that since you don't luckily have developed it.
This is my own knowledge and experience;
It can be stalled.
It can not be reversed once it is developed but, can still be hopefully stalled even after developing to a significant level.
The only way for stalling and stopping the progression is not only keeping your HbA1c's in control but, very importantly your daily Blood Glucose Levels in control as given to you by your Endo Doctor.
Each person with diabetes is as different as finger prints and shows variations within time and that's where the Endo's role is important.
Your profile says you are T2.
General rule is that if one keeps the figures between fasting 70 mg/dl - 110 mg/dl and 2 hour post-prandial 100 mg/dl - 140 mg/dl, and but then again, these figures has to be established by an Endo for each person's particular case, and this normally provides the right track for not developing any further advancement for retinopathy.
Keep your blood sugar level within the range recommended by your doctor.