For those who are thinking of applying for permanent residence

One of the requirements for applying for Permanent Resident is that you must be staying in Japan with the longest period of stay for your current status of residence.
Each status of residence has its own period of stay.
For example, in the case of "Engineer/Specialist in Humanities/International Services", the period of either 5 years, 3 years, 1 year or 3 months is permitted.
Therefore, when a person with a status of residence of "Engineer/Specialist in Humanities/International Services" applies for permanent residence, it is necessary to be permitted a period of stay of 5 years.
However, it is stipulated that "For the time being, if a three-year period of stay is permitted, it will be treated as staying with the longest period of stay."
So, if a period of stay of three years is permitted, this criterion is met.
Therefore, a person whose status of residence permits him/her to stay for only one year will not be able to apply for permanent residence, even if he/she continues to stay in Japan for ten years or more.