How exactly do upgrades work? Do they know at the hotel before you check in that you are getting an upgrade? Or do they simply see what is available when you arrive to the hotel?
Do Platinum Premier members get consideration over Platinum Elite? Does Platinum for Life status get consideration over Platinum?
Upgrades are normally made when you check-in. Platinum Premier is at the top of the list for upgrades, depending always on what the property says they have available. The desk Associates know your status, but many times do not volunteer an upgrade. You have to ask and maybe remind them what your status is. If not satisfied with the first response, ask for the Desk Manager/Supervisor or even the General Manager depending on the property's size. You have nothing to lose by doing that. Platinum Elite IMO would be next in line as Platinum for Life falls into the category. I would, however, mention I was Lifetime to see if that gave you any additional leverage because I don't think it shows on your reservation. FYI, my current status is Platinum Premier, but I am also Lifetime Platinum. Finally, I have been able to get upgraded via phone at properties that I frequent on a regular basis and I have read on this site of others who have been successful doing this. Good luck and happy traveling.
One thing I do is look at the hotel's website before checking in. I put in the day's date for a reservation and from there I can get a very good idea if I can reasonably ask and or expect an upgrade.
Also, I wonder when the upgrade is decided and if that's uniform. Clearly sometimes I arrive and they've thought out my room--nice high corner room or a suite upgrade without asking. Other times, I'm clearly just another reservation to them.
At the top and of the tree here is Plat Premier, a genuinely rare traveller representing only 3% of all Plats (not so rare here, we have about about a dozen PPs who regularly contribute) but they are (nominally) at the top of the upgrade tree. From PPs posting here, it's somewhat hit-or-miss as many front desk associates don't actually realise that Plat Premier exists.
THe more common Platinum is next in line on the upgrade list, followed by Gold. As is also proven, Silvers do end up with upgrades too, though the level does not require thenm to be on the upgrade list.
Note, there is no seperate category of lifetime platinums because lifetime simply means the member remains at platinum level for the remainder of their life without needing to requalify via the 75 nights. Lifetime Plats are Plats. That's it!