I was ready to quit BYM but then i tried this...... (ooops some thing broke)
If your are suffering from this. Change to your in private or incognito settings and BYM will run like a dream.
I have now attacked 3 wild monster bases and this message has not come up, it works on chrome and firefox.
Please don't ask why I was in in private/ incognito mode. Honest i was buying a diamond ring for the wife
Try it, it might work for you too
Happy monster killing