✔ 最佳答案
What tricky about your case are:
1. Your mother is the actual owner, but not the official owner;
2. You provided no detail of the ownership (how the government lease was written).
In this case, what you should do, at the least, is to prepare all the written information regarding the ownership (including Land Registry Record). Also, you should contact the Land Department and see if the market difference is needed to be paid when this lot is sold.
As soon as you have cleared everything, your mother should ask the High Court for a probate so that the lot can be inherited to your mother. Once, it is done, the concern of IRD will be resolved.
At the mean time, you should request extension to respond to IRD and pay all tax.
A friendly reminder - this problem has to deal with eventually.