My partner got a status match to Singapore Air Gold status last week using his BA gold and Turkish Airlines Elite plus status. Contacted thru their website and was asked to submit 6 requirements including travel history, flight statement, if one has corporate account and future trips with SQ with booking number. It was perfect since he was flying on SilkAir/SQ from Cebu to Melbourne in economy class and was able to use the Plaza Premium Lounge in Cebu. No upgrade as the cabin was full even in business class but was able to choose seat with more legroom