Unlocking from an iPhone 6 from Straight Talk under 12 months

I paid in full for my refurbished iPhone 6 July of 2018 through Straight Talk. I have been using ST service before I bought the iPhone 6 (15 months). I know their policy is 12 months or later of owning one of their phones they will gladly unlock the phone. I didn't do my homework and signed up for T-Mobile service (prior to finding out when I bought my phone from ST) and concerned that ST won't unlock this phone. I feel I have been a loyal customer to them and even bought 3 phones for me, my wife, and son. Has anybody had issues with them not unlocking under 12 months of the phone ownership.