Going multi-platform from the start is probably not the way to go as you are adding complication before you have the basics rounded out, but once you are spending that much on advertising you presumably have a sizable turn-over and should have long ago looked at diversifying to deal with situations like this which (even if temporary) could kill the business model.
Of course if FB is truly the only game in town for your target audience, you have a problem there...
Going multi-platform from the start is probably not the way to go as you are adding complication before you have the basics rounded out, but once you are spending that much on advertising you presumably have a sizable turn-over and should have long ago looked at diversifying to deal with situations like this which (even if temporary) could kill the business model.
Of course if FB is truly the only game in town for your target audience, you have a problem there...