Registering Rental agreement

Hi All,
My friend is applying for a dependent visa for his family. I know that Registered rental agreement is one of the documents. The problem here is he recently moved to a different address and he reported to commune and initiated address change procedure. The process is "In Progress", so his RP contains old address. Which agreement he has to get it registered. Old or New.
Logically he should get for new one but will the Belgian officials register since his RP contains old address.

Hi Dilip,

I am in similar situation.
Did you get any clarity on the issue?

I heard from one of my friend that they register the agreement if following things are there in your agreement
1. Your name
2. Your Resident permit number
3. Owner Resident permit number
4. All your roommates RP number and signature.

Hi Dilip,

Sorry my situation is a bit different:
My rental period begins tomorrow onwards but its a studio meant just for 1 person and its for 4 months in the lease agreement. Now if I get the residence permit with studio address and then rent another apartment that can accommodate 2 people. Will the visa processing with Residence permit with old studio address and lease agreement of the new apartment work without updating the address in the commune.