After 5 or 6 missions out of Tulagi and turning down at least 3 new commands, I saw an opportunity to transfer to Milne Bay, which would put me about 650 NM closer to the Celebes Sea, the usual destination from Tulagi in May 1944. After starting the first patrol out of Milne Bay I looked a the Nav Map to see where to mark the 10 Nm point out of Milne Bay. I usually scribe a circle around the base so I know when I'll be close enough on the way back to anticipate the end of patrol notice.
There was no Home Base designation on Milne Bay, or on any US Base marked with an anchor. No tilted anchor anywhere. Period. I did get into the patrol, reaching the Celebese Sea as directed, but then realized I'd never be able to end the patrol. So I reloaded a previous Save that put me back in the office on Tulagi, and tried a transfer to Midway. That went just fine, with Midway showing the tilted anchor.
Very strange. I suspect a file problem on the new Milne Bay Advanced Base. I leave it your capable hands.