In Vietnam, it usually takes about 3 years for the IP Viet Nam to issue a fist Office Action.
The JPO and the IP Viet Nam started the PPH program from April 1, 2016, and under the PPH based on the Japanese examination result, a first Office Action is issued within about 10 months.
However, the IP Viet Nam limited the number of the PPH request up to 100 a year. Hence, the requests for the PPH based on Japanese applications reached the upper limit promptly, just after 2 days after the initiation in 2018.
Under the circumstances, the IP Viet Nam increased the upper limit to 200 a year (which I believe is still not enough…)