EAD can be applied with or after 485 is filed. Only for EB1, 485 can be filed with or after 140 is filed. However, once this EB1 140 was ever rejected, the 485 would be invalid immediately as well . That's the risk to use an EAD without an approved 140. If you desperately need this EAD, you could file 485 and EAD now. Bless your 140 get approved soon!