Yes, the code
fix was posted in a specific thread in our support forums (which I realize you won't be able to access in full unless you are a verified customer), but using the instructions from the development team member + the latest version of Vantage v1.1.2 should resolve the issue with the postcode search. Thanks for helping see that was happening, by the way ;)
An extract from the thread explains why the issue was occuring:
This will ensure small radiuses dont get rounded down to 0, which is what is happening the case for "BT9 7DP". If you also change the .65 to .75 or .85 or more, it will grow the radius created in the auto radius calculation. Whats happening in this geocoded search query, so you understand, is that whatever you type in the "near" field in the vantage search gets sent to Google Maps Geocoding API, and API returns coordinates for the location matched as well as "bounds", which is roughly the equivalent of the square of the map you would see if you had typed that postcode/address/city into a normal google maps search. We take the distance from one corner of that square to its opposite corner, then multiply by .65 to get a rough approximation of a circle (for a radius) that encompasses those square bounds. Thats where modifying the .65 to a larger number would result in a bigger circle radius being calculated from the bounds distance.