Restricted Bidding Amounts in an Auction

[2307m]

I came across an Item this morning that I wanted to bid on with a starting price of £25 plus BPF.  There was only 6 minutes left and no bids, so I went to the bid box and instead of being able to enter my bid value, I was given three incremental bid offers - £27 ; £28 ; and £29, but I was prepared to go higher than £29.
Thinking there must have been a glitch, I logged  out and logged in again but those three values were still there.  Trying to figure out what was wrong took precious time so I selected £29 and was advised I was the highest bidder. Then suddenly, a £31 appeared and the time had gone, so I lost out.  Does anyone have any idea what caused this.  Thanks. 

[*vyolla*]

Underneath the 3 buttons with recommended bid prices you can select, there's an option to put in your own maximum bid price if you prefer:

[tommystrezures]

In addition to the above there must have been an opening bid at £25. That buyer obviously has put a max bid for example of £35, so when you placed your bid of £29,  it’s incremented up to £31. The other option your bid was placed first and a second bidder placed thei bid within a second or two of yours but higher. Without seeing the bid history of the item we cannot give you a definitive answer.