I'm about to push the "buy" button on a Ribble Winter Audax, but still deciding between a 50cm or 48cm. Both have horizontal top-tubes, but I am unable to get hold of the geometry for a 48cm frame size or standover heights for any of the sizes (have contacted Ribble already...).

I'm not the tallest cyclist (5ft 4). I was properly fitted a few years back, so understand geometry, hand, seat leg positions etc. and trying to replicate my main bike. The head and seat angles of the Ribble Audax 50cm are identical to my sunday best, but Ribble are unable to confirm the geometry of the 48cm frame. So, I'm more inclined for the 50cm but need to check the standover height before I go for it. I currently have no problems riding a classic horizontal top-tube fixed gear bike so high bottom bracket, with a seatube of 49cm c-c. The standover measurement from the ground to the top of the toptube measures 75cm and the family jewels are fine with this.

Does anyone out there own a 48cm or 50cm Ribble Winter Audax bike and know what the standover heights and actual measurements are so I can choose the correct size? Thank you!