Just bear this in mind: the police have got far better things to be doing than chasing up someone who may have painted a toy gun 3 days before they had a definite defence against prosecution for having done so, which defence they gained by turning up to an airsoft site with said gun, especially since the intention to do so is the defence, in this aspect of the law, but also since the Association of Chief Police Officers have said the law is unenforcible (hence our hypothetical coppers would have a bit of explaining to do when their arrest record for the week was scrutinised). Plain and simply, nobody who understands the law can take it seriously and, by definition, anybody who attempts to give you grief about it doesn't understand the law so fuck 'em...
Just don't be a dick with your AEG, whatever colour it is, and you'll be fine. Naturally, should you decide to test the limits of what "being a dick" entails, it will not be contravening the VCRA for which you will be arrested, but any of a string of firearms and/or public order offences which existed before and will exist long after the VCRA has been quietly superceded.