[T-Mobile LG V10 General] Refrigerate:
Hopefully my experience isn't too old to be helpful now. I paid UnlockBase to get the SIM unlock done about three weeks ago, shortly after Maverick-DBZ- confirmed they had a solution in place. In my case, I was never able to get T-Mobile to say I was eligible to unlock, but the info I did get from different reps was not always consistent anyway.

I'm in Canada using Koodo. Bought an unused V10 (H901) from a U.S. seller on eBay and did not ever have it connected to T-Mobile's network. I checked the IMEI on the T-Mo site first, to make sure it wasn't stolen, then before ponying up the money for a pricey unlock, I tried a few approaches with T-Mo support to see what they might be able to do. Spent almost three hours on the phone in total being passed back and forth to reps in pre-paid, monthly, business, and tech support departments. Overall, the best direction they came up with seemed to be from the couple of employees who suggested contacting a third-party unlocker. So I gave up on the company approach and went with the outside solution.

I'd suggest using the link earlier on this thread that specifically talks about recent T-Mobile phones and the unlock app. Otherwise it will probably be difficult to find. I ordered the SIM unlock from the UnlockBase page on a Sunday evening, and just a little under two days later, I received the e-mail telling me it was successfully unlocked. With just an internet connection via Wi-Fi on my home router, I then launched the T-Mobile Unlock app that came pre-installed on my phone and it gave me a success message and deleted that app when I rebooted.

It's not as cheap as on previous phones where I was able to buy unlock codes that I entered myself, but these folks do seem to have a successful path to get the device white-listed so the native app will unlock it.

---------- Post added at 12:57 AM ---------- Previous post was at 12:31 AM ----------

...what I believe that all means in your case, is that the unlock app should work fine over your local Wi-Fi once the phone is successfully white-listed at T-Mobile. If you can manage to eventually get someone to understand and add it to the "unlock eligible" list, you shouldn't need to hold your arm over the U.S. border to catch an American cell tower signal.

The only other tricky problem I found was getting my mobile data working. Koodo confirmed I had added their APN correctly, but was unable to get me connected. They eventually gave up and told me I had an unsupported phone that they couldn't guarantee would be able to get data service at all.

I finally found that changing the default network mode setting from GSM/WCDMA/LTE to GSM/WCDMA got me a solid connection at 4G speeds. My thinking is that it's because I cut down my old full-size SIM to fit the nano tray in this phone. This older SIM probably doesn't have the info it needs to connect to Koodo's newer LTE band. I will probably buy a newer SIM from them eventually, to see if LTE starts working, but it's certainly in the good enough zone for now.

This is not likely an issue most people would run into, but I thought it would be worth mentioning somewhere, as it was frustrating to get past.