ipv6 firwall address lists timeout not work?

RouterOS General
1

  1. use terminal to add a address with timeout:
    /ipv6 fir add add list=oldV6 address=fec0:: timeout=2h
    The address list shows Dynamic and Timeout=01:59:59 and not count.

  2. use winbox to add a address with timeout, the address list shows static and timeout did’t count.

I’d like to know if it is my problem or a software bug?