best way is, in your mylearn portal ,my transcript area. Right beside your certification expiry date, there's a renew button, click on it and all the possible options will be listed.
I think you should be OK to take VCP550 exam to renew it for another 2 years, or take any other VCP certification exam like VCP-cloud or VCP-DT before current VCP expires and passing any of those will also renew your VCP for additional 2 years period. (in short your all VCP certs will be lined to one expiry date which is expiry of last VCP exam that you have taken)
you will be able to take VCP6-DCV Delta exam too
this will be upgrade, if you wish to go for it.
Answer of question is Yes.
I am completed agree with Scott, it is wise advise.
oh yes, VCP550D, the delta exam could also be an option.