I have been thinking over what Dave and Jim have said about booking Ewan & Peggy and the time of performances. I can't swear that they asked to perform for the full evening; but it seems likely to me that the contract probably called for the same 30 + 90 minutes which Dave mentions in his post.
Now I saw the pair three times in two Sussex clubs - both Sunday night clubs in pubs with a strict 10.30 pm, no drinking up time finish.. Both these clubs started at 8.15 and would have had a 15 minute interval leaving 120 minutes - the time the the guests were asking to perform!

We moved to Brighton in 1968 and started a Wednesday club straight away in a central Brighton pub. Looking back the situation seems unbelievable, but I can assure you that it is true. The Brighton licensing laws called for a 10.30pm closure on Suns and an 11pm closure on Fris and Sats. On Mon - Thurs pubs closed at 10.30 apart from a 13-week "holiday season" - effectively June to August - when they closed at 11pm. This meant that for 9 months of the year the club also had a 2 hour session. Actually, we started at 8pm but as in all the clubs that I have run the first 1/4 hour was of residents playing tunes.

What made the situation even more ridiculous was the fact that Hove was a separate local authority in those days and their non-Sunday closure was 11pm all the year round. Our first flat in Brighton was only one block away from the sea front, but also very close to the border with Hove. We had 3 pubs in our street, two in Brighton and one in Hove. We would often be having a drink in our local and if you were in a good conversation, around 10.25 someone would say, "Does anyone fancy a 'Hove pint'?" and then we would toddle 50 yards along the road for half hour's more drinking.