Have you seen this here: https://www.thestudentroom.co.uk/sho...d.php?t=223269 ?
I think it might really help with your question
I've also now popped your thread into Law
If you don't think this is the right place - please let me know!
All the best,
See : https://ipsaloquitur.com/contract-law/consideration/
And : https://ipsaloquitur.com/contract-la...sory-estoppel/