11pm EST? because that's 4am for me, I doubt that'd be manageable. If by the off chance I'm awake, I'll message you, but I'll most likely be asleep.
I know you haven't specified that you'd be available then, but from 9:30pm BST to 12AM BST I will definitely be available. Any later I'm uncertain of.
If today isn't manageable, then tomorrow 10AM EST/3PM BST is great for me