Hi Drew re Milk Cows when your in your Campaign you should see replemishment ships in Spanish Ports Cadiz & Vigo also off Canada & Mid Atlantic look at your Mod Data Campaigns Campaign file in the mission editor then ( May need to do it as administrator) look for the blue land bases icons & blue uboat icons click on them to see when they appear & disappear then just make a note in a notepad for future reference.
In your campaign game when you head to the Area of the Milk Cow it should show up on the Navigation map
when you get to 1000mtrs away press escape & it gives you the Option to dock at U-461 or what ever the Milk Cow
uboat is called if you use the Commander mod when you dock at the Milk Cow & exit your game & reload the Commander Mod you can set days spent in port to 1 day click Apply so its Activated then when you restart your Game with the Commander Mod 24 Hours have passed & your near to the Milk Cow with fully Replenished Fuel & Torps
Screenies below from GWX your Milk cow positions maybe different due the Mod your using
