Tls

[BIll]

Like you Highbury, last one bugging me. In my early youth I was a fan of Billy Bunter so thought this would be easy enough, but it has pulled me up short. 10a. With singular Greyfriars master education's suppressed (9). I have S?U?L?A?D, unless, that is, I've made a mistake with 1d (musician - musin(g) round cia) which I admit I can't satisfactorily parse given the German connotation. Help would, as usual, be much appreciated.

[Lie-in King]

Squelched - 's(ingular) Quelch ed(ucation)'

1d German, say, endlessly entertaining about spies (8)

Yes - Musician - '(a)musin(g)' (endlessly, round) 'CIA'

https://en.wikipedia.org/wiki/Edward_German

[BIll]

Ah! Many thanks pal. My real error was with 9d for which I had 'man' as the first word instead of 'the'. Silly, unthinking me!

[Lie-in King]

You're welcome :-)