As many seem to wonder about details, this is my understanding of the situation (I've posted some below, but this format would be better): - 070, 080 and 090 p

As many seem to wonder about details, this is my understanding of the situation (I've posted some below, but this format would be better): - 070, 080 and 090 prefixes are being used for mobile phones and M2M (machine-to-machine) communications since 1999. They are 11 digits long and the future shortage was expected. - 020 prefix was created exclusively for M2M in 2017. The existing M2M numbers do not have to migrate, but it is recommended for most cases as 020 prefix has no requirement for the number portability and QoS. So the creation and expansion of 020 prefix is irrelevant to the population estimate. - Since 0204 prefix was already used for pagers, and since 0 is a trunk prefix in Japan, there were initially 80 million numbers available, starting with 0201--0203 and 0205--0209. - It was envisioned that 80 million numbers do not suffice for the future expansion of IoT devices, so there was already a plan for 13- or even 14-digit numbers at the time. Note that while 14-digit numbers are within the E.164 recommendation (e.g. +81-20-XXX-XXXXXXXX = 020-XXX-XXXXXXXX) it does seem to cause some serious engineering problems to tackle. - 020 prefix was allocated in the increasing order, so numbers up to 020-536-XXXXX are allocated as of May 2019 [1]. It is expected that the digit expansion will happen in the remaining area. - While 020 will greatly postpone the exhaustion, existing 070--090 prefixes would be eventually full in the future. 030, 040 and 060 prefixes once used but now vacant are reserved for this inevitability. [1] http://www.soumu.go.jp/main_content/000477284.pdf http://www.soumu.go.jp/main_content/000477284.pdf