Hi Lcdr the SH3 Stock Campaign convoys are written in the random leyer those convoys spawn every 72-225hrs even if those waypoints stop 100-500kms from Halifax and that convoy disappears it will respawn 3-8 days later you can go into the SH3 Mission editor and enter your own convoys with longer waypoints and have all the ships spawn all of the time
if you have GWX3 installed you could try the steel sharks GWX Campaign all the convoys are in the scripted leyer and the ingame radio messages of convoy sightings are real the convoys are there in that grid at that time of the radio message being received the campaign SCR file is very large 15,000kbs plus
some convoys have 90 plus ships in them
theres two campaign downloads one is war start 1939-1943 and the last one is
may 1943 onwards
also GWX3 has more ship types escorts and merchants
info on the steel sharks campaign
http://www.subsim.com/radioroom/showthread.php?t=236077
SH3 Stock Campaign
LND 209kbs
RND 5915kbs
SCR 2652kbs
Messages eng 6kbs
if you would like help adding Convoys to your Stock install I can help you but stock SH3 has very few ships in its ship roster for all nations