A reply from Forum Staxexchange.com
You probably aren't considering legal recourse, but,
assuming a common law jurisdiction, it is surely helpful to know that
the law is probably on your side here.
Knowing the law can be quite convincing in its own right and might well be useful when trying to persuade someone higher up to act reasonably and fairly.
Equity is a body of rules which modifies common law, including contract law, in the interest of fairness.
As long as you haven't done anything untoward, you can avail of the remedies equity offers.
There is a rule of equity called
promissory estoppel. It protects those who act in reliance on a promise, even when a contract does not exist.
Contract terms that allow cancelling leave aside, in booking tickets and hotels on the basis of confirmed leave, you acted in reliance on a promise of leave on given dates and are entitled to compensation.
Common sense and a basic idea of fairness should have been enough to persuade your line manager that there was something wrong with how you were treated here.
Meet with your manager again (or with HR or someone more senior, using your best judgement to choose),
explain your situation once more, and mention your legal right to be put in the position you would have been in but for the breach of promise (much as the employer did in
this answer given previously);
this may work where common sense has failed.
Unfortunately, any conflict with the hierarchy will probably be noted; standing up for yourself in a corporate environment is rarely entirely consequence-free.
(Note that this doesn't take away their right to cancel leave that you say your contract gives them - promissory estoppel merely recognises that you reasonably acted in reliance on assurances - assurances that were withdrawn - and that you should be compensated for the losses thereby incurred.)