If you are happy with $12.65 then I would suggest selling on market now.
There's only a ~5% difference between the indicative offer price $12.65 and the current SP $12.05 after today's jump from the news. 5% is not a lot of extra benefit for waiting what is likely to be months for the transaction to complete, and during which time there is more chance of significant downside from the transaction not proceeding than there is chance of significant additional upside.
