Em how frustrating for you. I hate the waiting for emails or fur anything to happen really!
I asked Dr M about transferring embies 1 or 2. She said 1 in 5 chance you will get twins and they sit 60 to 70 % success rate and I think she said it drops 5 % if you transfer 1 embie.
Afm I never heard from the clinic yesterday so obviously not going in for a day 3 transfer. But I also don't know what's happening with my embies. Kills me not knowing. Got to remember to not stress.