@Layla123
@NuttMegg
Per NK's 8/16/18 Interview with CBI, she told him to pawn the rings on Monday during the day or evening, Discovery page 575. Per her interview with the Denver Post, she said she didn't even consider Shan'ann had done anything but left for the day at that time, and wouldn't have thought she was missing until Tuesday, but on Monday evening she saw the news reports about the pregnancy.
There is a screenshot of recovered texts about the wedding ring that would have a timestamp, but I cannot locate them.
ETA: There is a call log of a 51 minute long call between NK & CW from 11:09 on Monday (8/13) night, and then shortly after midnight NK googles regarding the missing Shan'ann, and then has a call of 10 minutes early Tuesday (8/14) morning at 2 am with CW. At 9:30 AM Tuesday, CW puts the last photo of NK into the Secret Calculator app. At noon Tuesday, NK googles the case for 4 hours, and at 5pm if "cops can trace text messages". She reports that Tuesday was when she initiated her data deletions. On Wednesday morning 8/15/18, after speaking with her father, NK contacts LE for the first time. From several different directions, evidence mounts, a confession (partial) emerges, and CW is arrested Wednesday evening.
The call/text log information is gleaned from the digital data timeline at the end of the Discovery document. I cannot cite page numbers at the moment.
There are day/date match errors throughout the Discovery from various sources. It appears that NK says she facetimed with CW Monday night, which may be the same as the 51 minute call, I couldn't say.