How did you get your APRC? If you got it based on your employemployment, your APRC is still valid, so you can apply for reissueance at NIA.
If you got your APRC based on marriage, it may be already canceled, unless you applied for an APRC leave extension that @owleyes asked.
if you would return as an employee, you qualify from day 1 via the company. If not, you should wait for 6 months.
[Added: If you have an enrollment record within 2 years, you qualify from day 1.]
[Added 2: if what you did is a suspension, you qualify from day 1.]
You may get more reliable answer from TECO or NIA and NHI. you can ask them directly by phone or mail.
Relevant sources
validity of marriage based APRC
Immigration Act
Article 33
National Immigration Agency shall revoke or repeal a person’s permanent residence permit and cancel his/her Alien Permanent Resident Certificate if the person meets one of the following circumstances:
…
4. Has not resided for one hundred and eighty-three (183) days for each year during his/her permanent residence in the State. The person shall be exempted if he/she has the approval of National Immigration Agenc
…
validity of employment based APRC
Act for the Recruitment and Employment of Foreign Professionals
Article 18
Where a foreign professional, after having obtained approval for permanent residence from the National Immigration Agency, Ministry of the Interior, leaves the State for more than five years without re-entering, the National Immigration Agency, Ministry of the Interior, may revoke said person’s permanent residence permit and cancel said person’s Alien Permanent Resident Certificate, and the provisions of Article 33 Paragraph 1 Subparagraph 4 of the Immigration Act do not apply.
NHI
https://www.nhi.gov.tw/english/Content_List.aspx?n=4393D5216F6416B4&topn=778856C209BCE527
Resuming Insurance after an Extended Stay Abroad
- Those who do not have a record of being insured under the NHI program in the two years prior to their return to Taiwan are entitled to get coverage under the NHI system six months after establishing their household registration.
- Those who were abroad for less than two years are qualified for the National Health Insurance as long as they still have their household registration and must enroll in the National Health Insurance program according to the regulations.
suspension of NHI
https://www.nhi.gov.tw/english/Content_List.aspx?n=1E7F01DB3BBD5079&topn=778856C209BCE527
What to Do If Going Abroad for More than Six Months