Level 351 - that's me done then
Level 345 is I suspect impossible without additional help from boosters and extra turns so I acquired some, very much against my principles in the hope that it was a one-off. I don't know whether level 351 is possible with additional help but I am absolutely certain it is impossible without it (and it should be obvious to the designers why!) so, as I'm not willing to part with any more cash and King, unlike all its other games seems to have no plans to make free boosters available, I regret that it sees the end of my involvement with the game.
It has been by far the best of the King games to date providing a balanced combination of skill and luck and I have done very well passing every level up to 351 with 3 stars so it is not a game that I willingly give up. But one can only flog a dead horse for so long. King, it seems, just can't help pressing the self-destruct every now and then.