1.1 Foreign national applicant must hold a passport that bears a Non-Immigrant Visa and was granted with one-year visa extensions which reveal that up until the date of application submission, the applicant have been staying in the Kingdom for at least 3 consecutive years.

How does the immigration review this criteria?

Does the applicant need to have 3 consecutive one year extension or 4?

You guessed ... I want to know if I can apply now ... or next year ...

You must have completed three complete years in that status is my understanding so you would be on your 4th.

1.1 Foreign national applicant must hold a passport that bears a Non-Immigrant Visa and was granted with one-year visa extensions which reveal that up until the date of application submission, the applicant have been staying in the Kingdom for at least 3 consecutive years.

How does the immigration review this criteria?

Does the applicant need to have 3 consecutive one year extension or 4?

You guessed ... I want to know if I can apply now ... or next year ...

technically it is not a 1 year "visa" extension, it is a 1 year "permit of stay" extension.

seems even immigration don't know the difference in terminology between a visa and a permit.

this is a typical scenario for many expats working in Thailand :

board aircraft and enter thailand with a single entry non immigrant visa with 90 day usage validity

get a 90 day permit of stay stamp from the immigration officer at the airport

get a work permit

get a 1 year permit of stay extension for 3 consecutive years on the basis of having a work permit

if you need to travel in and out of thailand during this time, get a re-entry permit, this will ensure that your 1 year permit of stay extensions are not forfeited.

Thanks.

I got one more year to prepare then.