Lost HD signal

I have an HR 24 and slimline 5 LNB. I've noticed for the past two years that from October to May, I lose my almost all of my HD channels. I've had two installers come out and reposition the dish to no avail. Once May kicks in, everything is great. I share my service with my cousin who lives in Cleveland. I'm located in Oakville ON. I'm wondering if it's the change in the Earth's rotation which happens as we progress thru the year and I lose sight of the HD sats. SD is fine.

Here are pics of my signal strength and meter
















Any ideas or fixes? The dish in anchored into the upper level of my home with clear line of sight to the sky.

 

Here are the signal meters

 

It's my only receiver. No multiswitch (ie splitter if that's what a multiswitch is)

Works perfectly in spring & summer and loses HD fall & winter.

 

I believe I have a DirecTV Slimline SL5 KA/KU 5 Satellite Dish with 1 coax required for each tuner. Should I upgrade to the DirecTV Slimline SL5S SWM DECA MRV 5 Satellite Dish?

 

Sorry, wasn't trying to break the rules. I pay for the account. I know of many people who have residences in both the USA and Canada (snowbirds for example) and they want access to their account year round. Is this illegal too?