To the UK users.. In case you have not spotted it, over in the tips & tricks section there is a thread "Using outside the US, where folk have figured out a (fairly) easy way of setting Echo to finally be set to the correct timezone. The same method could potentially sort out the location issues also and be set for your postcode, but we're still working on it (so far not no luck there). But I'm chuffed I can finally ask Alexa the correct time!
One positive thing to note though, is the Alexa Api clearly contains codes for all timezones and country codes, which gives me hope that full international support may just be around the corner.