The most correct answer is that you should still be engaged in some sort of soft power activity and should have proof of that.
Currently, I haven’t seen any reports of people being asked but it is within their authority to request up to date documents in order to grant you entry.
Arguably if they were to crack down on DTV holders at some time, the easiest ways would be through bank statements and proof of still being engaged in a soft power activity or remote work.
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