Finally got my hands on the new Airfix Blenheim Mk.IVF this week. It seems to have been well worth my waiting for, brilliant looking kit despite the issues with the bulged engine nacelles. Some optional bits, namely 2 types of rear-firing undernose turrets which hints at other variants in the future.

The kit includes both single and twin gun turrets and while welcome, I found a small problem. The guns provided to make up both turrets are Vickers K's but I'm pretty sure the twin installation should be Browning 303's. Certainly every photo I have shows Brownings, while the Vickers was standard in the single gun turret of the Mk.1.
So my question is, have Airfix made a fudge up or was it an earlier and rarer weapons fit?

Thanks in advance.

Stephen.