A message of sympathy.
A decade ago this was us. DS had been rejected by Cambridge, lost interest in his fifth choice and was waiting on Warwick, UCL and LSE.
Like your DC he had top grade predictions in the right subjects, and effectively this was his first experience of "failure". All his friends were sitting around the sith form common room talking about accommodation and plans for the following year and he was stuck trying to focus on mocks and A level revision whilst waiting and waiting.
I will confess to phoning UCL admissions without giving my son's name to ask when he might hear. As a mum I needed some help in supporting him. They were kind and gave me the date they hoped to make final decisions. I also made the most of being an LSE graduate to attend a talk by the then LSE Director, and asked a question/rant about why they were treating 17/18 year olds so badly. It does not seem to have made much difference.
In the end he was rejected by UCL and Warwick but got offered a place at LSE towards the end of March. In those days it was down to PS scoring and with fine margins we think the fact he was registered to attend LSE lectures and did so regularly may have given him a slight edge. Someone else at his school was rejected by all four, but on reapplication was offered a place at Cambridge.
In retrospect I am pleased that DS had his first experience of rejection when at home, where we and his school were there to support. There has been plenty more down the road. The maxim that you only need one place is true. DS was offered a place at Oxford for his Masters (he chose to stay at LSE) and received a funded PhD place at a US University with a similar world ranking. He is now at another similarly ranked University. In short he, and many of the others who faced rejection were good enough, but it was a numbers game. Demand is huge.
@Schlappe I am interested in your comments about the course revamp. DS' observation was it was not the course structure that caused problems but the maths content. I assume that, given the direction of travel in economics, this has not been watered down. Most vulnerable were students, often from East Asia, who had been intensively tutored to get top A level grades. One boy he knew was already throwing all night sessions in his first term in his struggle to keep up, whilst another girl who had managed six A levels, was really struggling with the compulsory maths courses required as part of the second year. In some ways the old course structure worked well as the toughest courses came in the second year, with scope to fail and repeat the year rather than fail the whole degree. This girl scraped through and was able to then select options that suited her better (economic history etc) and with a lot of hard work somehow managed the all important 2.1. She was not a mathematician and had wanted to study Liberal Arts in the US. Her dad, who was paying, felt that a degree from the LSE was too prestigious to turn down. I hope that TMUA allows the LSE better scope to identify potential and to fine tune its admissions.
Good luck to all and I hope you hear soon.