@Linkzor, assuming iMessage activations weren't a concern, the way I would operate it as:
- Disable the 2 Degrees SIM.
- When I am expecting a 2FA, attach to wifi, turn on Flight mode. Enable the 2 Degrees sim and wait for it to attach using Wifi calling.
- Once I've got the 2FA, disable the SIM. Turn off flight mode.
This *will* work, however fully acknowledge that this is a hassle which is why I tend to just pay $5 (AUD) a day for daily roaming.
