A quote from Team Nuts's facebook.

The NanoTwo V3s were forcibly discontinued when the small OrangeRX receivers which they were based around disappeared. Many other DSMX/2 RXs are also being discontinued at the moment, so to avoid all that, the NanoTwo LT is essentially a NanoTwo V2 (which was a cheaper and more reliable design than the V3) with servo leads attached allowing you to use your RX of choice. This should work well for many BBB teams looking to upgrade their kits.

They will be appearing for sale soon. Since the bulk of the manufacturing has been done already, stock levels should also be more reliable now.