Do we know why boarding gates are announced so late at LHR (actually many UK airports seem to do likewise), while other airports are able to allocate gates far in advance? Given paper boarding passes have a space for gates to be printed on them, i assume British airports are an outlier. I've heard suggestions its because of how constrained LHR is and how often provisional gates would have to change that it'd cause more problems than it solves; and that airports want to manipulate passengers into spending more time/money in central retail areas rather than going to their gates. But it all seems rather speculative.