It's a 1989 model although it would have been available to buy in 88. The strange part you mention near the crank is a U brake. Note that it has no brakes mounted on the seatstays as you would normally expect to see.
These all had U-brakes in 1988 didn't they? The colour scheme matches the 88 Catalogue, not the 1989 one. The catalogue says that the 15" frame model had 24-inch wheels, which does not appear to be the case on this model, so it is likely the 17" as stated.
Seat post is hopefully inserted only a few mm in the pictures, else its somehow been bent.