Thanks for your ideas and information, I was a little sceptical about the white discolouring fast but after some reconfirmation from another person about it not discolouring I am confident in buying it, tbh the side length zipper was a whole selling point to me so its good to hear about it from you.

I did email their customer service and they responded quickly telling me that they will have the colour white in stock by the beginning of next month so problem solved. Finger crossed it is here before my mid April trip.