This might be a very well-known quirk, but I've not booked anything on the website for some months.

Tried last night to book two Y returns to Warsaw in May; price on the (new) website was popping up as about £425 - I couldn't get the older one to load. This was some £30 higher than the actual combination of the ticket prices, with mystery fare costs coming from nowhere on the payment page.

In the end I gave up and booked through the app, which was consistent with the prices shown on Google flights - for about £345. Not taking issue with the price - we needed them for a particular set of dates - but how on earth can the app and the website not only have different prices, but the website seem to add extra charges onto the listings on the individual pages? I wonder if this is fares not being loaded into the same platforms at the same time, but it struck me as wholly unhelpful and I'd have been really quite annoyed if I didn't have the sense to check the price on the app instead.