The 1897 pictorial set was overprint vertically or horizontally for postage due purposes. But in 1901-02, a short set of the 3c, 5c and 8c including their colour shades were overprinted locally at Sandakan for use and this time, the overprint included a "stop".
These three stamps have the unrecorded "raised stop" variety. The 3c has been in my collection for some years and then I managed to find the 5c mint last year. The third stamp was bought by someone on ebay a few years ago but problem was that I did not notice the error then. But then the double ring cancellation was either fake or a late contrived cancel by favour. A one off error may not be accepted as consistent. But here we have three clear examples and so it is about time it is included in the stamp catalogues.
Included here are the 1897-99 and the 1901-2 8c overprints. The second stamp has the stop after "postage due" and was well used from Lahad Datu. Above them is the 1901 3c with stop in the normal position. It looks like a double overprint.
These 2 postage dues are from the earlier 1895 set. The second stamp has a stop after the overprint but it seems a bit further away than normal. It would have to be compared with another good example to make sure it is authentic and not a blot of stray ink.