12CR2 Tables with named NOT NULL constraints cannot be recovered with the REMAP option

Hi Professors,

I just checked Oracle 12CR2 RMAN new feature. One of them is we can use RMAN to restore and recover a table to point of time to another schema by using REMAP. But one limitation is "Tables with named NOT NULL constraints cannot be recovered with the REMAP option". I am a little bit confused for this. Dose this mean the table we want to recover can't have any column with NOT NULL constraint? or the table can't have a constraint named   NOT NULL?

Case 1:

table_a (

id int NOT NULL,

name varchar2(30)

)

Case 2:

alter table

   table_a