Catalyzes the exchange of an acyl for a long-chain alkyl group and the formation of the ether bond in the biosynthesis of ether phospholipids. a 1-acylglycerone 3-phosphate + a long chain fatty alcohol = 1-O-alkylglycerone 3-phosphate + a long-chain fatty acid + H(+) Glycerolipid metabolism; ether lipid biosynthesis. Homodimer. Belongs to the FAD-binding oxidoreductase/transferase type 4 family.