I'm SPG plat until 2/2018, but have 9 more nights to go until Plat-50. The main benefit of Plat-50 is the 10 Suite Night Upgrades.
(Most SPG stays i get a free suite upgrade, but when traveling with the family, it's more mandatory.)
1) Is it possible to buy a SUNs for 2017 instead? Are they transferrable?
2) If I have another SPG card from a relative at my home address with 5-10 nights, then are those nights transferable?