I wanted to chime in regarding the network registration of devices and SIMs. We sent some products to our customer after registering them locally with the carrier. Unfortunately when they arrived with the customer, they did not connect and as a result, we had to instruct the customer to pull the SIM out of the sealed product and put the SIM into a cell because the devices were not registering in sufficient time. The registration was with the same carrier so obviously registration is required in different regions and may also take a longer period.
I would like to request that Hologram do a study to determine the registration times to expect so that device makers can set an appropriate timeout for registration instead of guessing the time frame required. In our case, the registration forms the longest power usage condition so we need to explicitly handle that in our design.
Another more complicated option to explore would be some sort of service-based registration through an API to individual providers so that devices are registered before them even being turned on.