Dear Dominik, According to Debian we will probably have to delete the British hyphenation patterns from TeX Live unless the licence changes. See: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=912557
In general it is becoming increasingly problematic to use custom (free-text) licences for each individual file. (It's problematic enough to keep up distributions of millions of different files with well-established licences, let alone having each individual lawyer check whether the licence in file X is compatible with the licence in file Y for N^2 combinations of those and ever increasing N.) A while ago we started suggesting the pattern authors to agree with the MIT licence, but some other licences might be acceptable as well (note that LPPL in particular is not acceptable for a number of projects). Best regards, Mojca