Uk ordering delays and cancelling..

[minga]

hi, i order my new imac fromthe uk education store on the 30/9, along with scanner printer etc. now after all the problems with card authorisation, it then said confirmed and then the computer was sent to manufacture. but i return to the store monday to see that the computer part of my order had been cancelled, and replaced with exactl the same spec pc futher down the page? is this an indication that there could be a change to the computer or is this common practice as i ordered a printer that had a 1-2 week wait on it, its due to ship this friday but im wondering if it will now?