NR disabled by UE, expected behavior?

Hi,

I have a doubt about the behavior of UE when NR is disabled on it.
Scenario:

  • UE attached to NSA network (dcnr=1 in attach request), so there is no NR restriction on network side.
  • from settings menu of smartphone, RAT is forced to 4G.

Now which is the expected behavior?

  • UE sends TAU request with dcnr=0

Or

  • UE reattaches to 4G with dcnr=0

???
(and viceversa, when 5G is enabled on UE forced to 4G, it has to send attach or TAU with dcnr=1?)

In which 3GPP specification can I find this?

I found TS 24301, but there are not specific informations about this.

Thank you for your support!