You're going to show up late in hopes of getting an upgrade or getting walked? In the former, usually those who arrive earlier have a better chance of an upgrade in my experience. In the case of the latter, the entire hotel needs to be booked & most hotels will try to walk a non-elite first so they don't have to payout per the T&Cs.

When I know I'm arriving late, either due to regular or delayed schedule, I normally (if possible) contact the FD to let them know.

Cheers.