Would being told that "there is no longer a current job for you, there isn't likely to be another job for you for at least another 3-4 years but no, we are not going to make you redundant" be considered as grounds for constructive dismissal, assuming that the affected individual decides that sitting around for 3-4 years is somewhat nugatory to a fulfilling career?
At first glance, and with a passing knowledge of employment law, there might some grounds however......
What I would say (and I s**t you not) would be along the lines of....
"Roger Copied.
Then you won't mind if my well paid job becomes my well paid hobby while I spend the next three to four years learning, developing and progressing my next career at your expense.
Out"
As I used to say when I was in (who knows, you may have heard me).
"You cannot be fired if you want to be fired, and if you are fired, you can only be fired once."