✔ 最佳答案
1. You should be fine. Even after an official name change, the former name will be still on file.
Basically, you can't "erase" the former name.
2. Yes.
3. Both. It does not make a difference. For example, if Mr. Chan Tai Man wants to sue the company, the case caption can be:
Chan Tai Man v. BCD Limited Company, formerly known as ABC Limited Company