Mrs Ultra, I think there is a wider point. DS was rejected by Cambridge in January and then we did not hear from his next three choices (UCL, Warwick and LSE) until late March.
Reading student room the following seems to happen. Applications are triaged with some accepted and some rejected early. The rest are sat on. This is more likely to happen for courses which are heavily oversubscribed and where many candidates will be credible Oxbridge candidates, and for those applying with predicted rather than actual grades. Durham, LSE etc need to get their mumbers about right, and need to give every candidate who applies before the UCAS deadline in January, equal consideration. So first they need to wait until there is some movement after Oxbridge offers. Then, especially where there are a large number of mature or EU applicants, they may need to set an additonal exam for some. (It seems that graduation certificates from some EU countries like Italy may not provide sufficient differentation as selection effectively happens after first year University rather than before entering University.) So they can't really score their remaining pool till towards the end of February. After that numbers are slowly whittled down as more places come up or some withdraw. LSE seemed to accept a few more each Thursday and reject some each Friday. (If it got to 4.00pm you knew you were safe for another week.) Durham in contrast, and from what others have posted about the wait, may hold on to their remaining cancdidates and make a decision right at the end.
In the end DS was accepted by LSE and rejected by UCL. Warwick, bizarrely, offered him a course in another department. Its fine as you only need one place and LSE probably offered the best course. However the long wait from October to the end of March was horrid, not least because it can add to the stress of exams. One boy he knew did not get anything, but did get Cambridge on re-application. There is now huge demand for some subjects in top Universities. Its tough. But easier, hopefully, if you expect it. (Says a mother with a DD applying for medicine!)