WHETHER DETACHED EMPLOYEES ELIGIBLE FOR PERMIT WITH UNLIMITED DURATION

Dear friends

I am here in Belgium since 2016 with family and have work permit B since the beginning. 
The work permit B and resident card are being renewed every year.

My salary is paid by my employer here, which is a locally registered NV company.  All my HR related matters are also handled by the Belgian employer and I am one of the director of the local NV company.  But I am not paying Social Security here.  Still paying  EPF contribution in India.  My present contract is ending in few months and there is no provision to extend it.

Recently I came to know that I am not eligible for Single permit for unlimited duration as I am a posted worker. But I have earlier saw in some forum that similar kind of employees were given Work permit A, which is valid for 5 years, when they renew it after 3rd/4th year.

I would like to have a work permit for longer duration and not connected with a particular employer so that I can secure a job  here.  Normally employers dont prefer to apply for WP B because of the cost, minimum salary stipulation and time consuming process involved in it.

Can somebody please advise me in this regard

Surya