Do you own the US ADR? Trustee to the ADR holds the shares. It probably won't relist if there is a hard ban, but the trustee should be able to transact the "real" shares in HK and settle the ADR. You might want to put your hands on a copy of the ADR trust and see what it says about a delisting.
I don't own any BABA now...Have had it before and did well with the company. The only China I now own is a small cap mutual fund (FEM). I am familiar with ADR...Own stocks from Japan, Canada, Israel, Great Britain.