What is the total capacity of the Lowland sleeper?
Glasgow : 22 First Class and 88 Standard
Edinburgh : 22 First Class and 88 Standard
Aberdeen : 11 First Class and 66 Standard / 11 First Class and 44 Standard
Fort William : 11 First Class and 22 Standard / 11 First Class and 33 Standard
Inverness : 22 First Class and 88 Standard
The ratios of First Class can be varied and I have shown the typical allocation
On the Fort William that is the MAXIMUM number of First Class, very often it is only 5 First Class with 34 Standard or 45 Standard (ie the south coach has both)
And is it equally spread between Edinburgh and Inverness?
As above, you can see the Edinburgh and Inverness have similar allocations, but they are different trains
Again, the number of First Class can vary
When I travelled on the Inverness - Euston sleeper last year it had just six First Class the other 16 berths were booked for Standard solo