I think realistically only £1m add-ons, but with a 15% sell on according to Darren. He's pretty much always right
All I can add to this (think I mentioned it before?) is the hold-up on the contract was never the initial fee; Plymouth were always OK with £2m. Their focus was the sell-on fee (smart CEO IMO). They wanted ~40% This was what we were negotiating.
Think about it, every 10m profit in sell on, at 40%, is £4m to them. Definitely the best way to bargain. Long-term planning. Well done Plymouth. That's the right way to negotiate.