"Nib shall expire 48 hours after the time-stamp of that player's last play, 24 hours after the time-stamp of the next play..."
You played at 16:04 on Friday, so 48 hours is 16:04 on Sunday.
RobH1 played at 17:34 on Saturday, so 24 hours is 17:34 on Sunday.
So, the earliest you can play is 16:04 on Sunday unless someone else plays, yet you played at 17:53 on Saturday. Explain your reasoning.