I would assume no.
If for nothing else, it would cause problem with the new way of gifting membership time by transfering membership from your account to the other players account. To me this looks like the system was not built to support a lifetime membership level for users since this would either 1) make lifetime members unable to gift membership or 2) make lifetime members able to gift an infinite amount of membership.
Both options seems undesirable since you either punish lifetime members or open up for abuse (i.e buying lifetime membership to sell membership time at lower rate or people "crowdfunding" one lifetime membership to get lifetime-ish for the whole group.). Sure, systems could be put in place to prevent the abuse, people could be banned etc but since PGCPoints was shut down partly due to abuse and the work with preventing the abuse I don't think a new feature with a similar abuse risk is at the top of the to do-list. :)
