One Year Business Visa Requirement, Renwal

[Devil]

One year working/Business Visa question, I coming up to a renewal end of the year and I have renewed before but.

One of the requirements in the countless documents required each renewal was that the company shows proof of employing a min x4 Thai National staff (makes sense), As in accordance with W-Permit rules etc.However Immigration require proof of SSF (Social security) payment each month for the employees paid by company. However what happens if the staff are no longer employed say 5 months out of the 12 and the company is currently seeking new staff and in Dec I will try to renew. How many months back do immigration check and officially check, do they want the last 3 month on submitting of SSF payments, 6 months or a whole year.

Appreciate any input.