Nowadays it is hard to grasp what is 'correct' or 'right'. Immigration included in the 12 month period of the ED Visa the 2 months of the tourist visa. So it was not possible to do 4x90 days fully. The limitation to one year seemed to be relevant because of the initial tourist visa.
Yes, because it was a former 2 months tourist visa that was converted to an ED-Visa. That's why no more possibility to extend within the country. Would have been different if the ED-VISA would have been issued abroad.
is correct. Next to all paperwork the language school compiled a complete documentation about attendance including photos plus a written test. No interview at the immigration.
After staying in Thailand for almost 5 months with SETV + extension (90 days) and one border run with extension (60 days) I got in Hanoi another SETV without a problem. They advised me to apply next time for a retirement visa. So I wouldn't generalize with the Vietnamese embassies.
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