net29091, if you make any programming changes, it will not affect anything. As far as SD is concerned, you need to tell them that you only have one residence. It's up to you if you want the primary as the cottage or your residence as the cottage. I would assume that you get your bills at the cottage since it's listed as the primary?
Under no circumstances should you mention to them that you have two locations, otherwise you are hooped.
Keep in mind that your "service" will be at the primary address so if you need a service call for any reason, it will always be at the location they have listed for you.
Shaw Direct "lost" all the information on the HAFH subscribers that registered years back. It's not actually lost but very few reps know how to access it so if you registered for the program years ago, they likely wouldn't know about it today.
If you want you residence as primary, just tell them you moved and give them your change of address. Tell them you installed the dish yourself, otherwise they will offer you an install.
By not being in the official HAFH program, you are not eligible for service calls to a second location so whatever is not primary will be on your own.
Don't worry about the receivers. You are allowed 6 in total. Any of these can be at your second location and SD will be none the wiser. As classicsat mentioned, if the receiver is unplugged or otherwise not receiving a signal, it will lose its authorization after a month. You should have the same dish at both locations so you don't run into programming issues. If both dishes need upgrading, Shaw Direct will do your primary and then you can just buy a second dish off Kijiji for your other location.