Hello.. Treatment of hyperthyroidism more specific graves disease with anti thyroid medications should be taken for at least 12 to 18 months for immunomodulatory effects of the drugs.. Targets are always keeping normal T3 and T4 and never chase TSH as it takes long time to come normal due to suppressive effects... It may take up to 6 months to yr also to come back normal so don't worry about TSH value..... U need to consult periodically to qualified endocrinologist Dm/DNB for your proper titration of doses and further course of action because its very common ppl mismanage this condition..!!!