Anyone actually ever seen one?
I'm not entirely convinced they even exist.
On the standard refund forms they say something like 'sleeper berths refund on form RSPxxxx'
any ideas?
The forms in question that must be filled out when dealing with Sleeper refunds are the normal Refund Claim Form RSP25805/24 and Confirmation of Cancellation/Transfer form RSP25911. The former must be completed in duplicate and sent together with the original tickets, the latter must be fully completed, certified and then attached to the Refund Claim Form.
I personally have never seen the latter, but then I rarely deal with Sleeper refunds. The FRPP still seems to be of the belief it does exist, so I'm sure it does somewhere. Most likely, stations such as Euston and Glasgow keep copies readily to hand, but I doubt you get much demand over at Merseyrail either and have therefore, most likely to of run out of stock and not applied for stock replenishment.