I have an old Hong Kong map (before 1940) which shows the east end of Kennedy Road joining Queens Road East just next to Wanchai gap Road.
As we know it is now it now joins QRE about a hundred yards further east just below Wah yan College.
When did this move did place and why?
I think Kennedy Road has always joined under the current Wah Yan College. See the following website (http://www.hkmaps.hk/mapviewer.html), and select 'Map 1889' under the reference map selection on the left hand side. Now zoom in to Kennedy Road. This shows a 1889 map with Kennedy Road joining QRE at the current position. N.B. Kennedy Road construction began in 1876 so this map is only 12 years after.
I suspect the map you have is 'lazy,' in that it shows the shortest route from Kennedy Road to QRE. On the same website select Map 1928 which appears to show Kennedy Road (as coloured in Red - as a first class road) joining QRE by Wanchai Gap Road. Even this Military Map appears, at first sight, to be misleading.
I didn't know what a lazy map was until now and indeed the map I have must be lazy. and thanks for the link to hkmaps.hk as it shows the actual map.
Gap Road, Wanchai
There may be another explanation. In the old days, the section of present day QRE between Stubbs Road and Kennedy Road was called Gap Road.
Some local document on this site had had that, with photos. Try to look it up using "Gap Road" including t the quote.
May be the map annotation meant Gap Road in Wanchai?
Extension of Kennedy Road Eastbound