what is the rationale for Dish to allows customers to sign up for protection in the same months that need service?
It's a loophole. Apparently nobody considered how people might abuse the protection plan... and for the most part they haven't ever truly plugged that loophole.
With the new 180 day requirement it is cheaper to pay the early termination fee instead of the $48 for 6mo.
wait... could you explain that math to me?
The monthly fee is $8 per month. Last I was aware, the penalty for early-termination (i.e. earlier than 180 days) is $25.00
So... IF 6 months (180 days) would cost you $48.00... One month would only cost you $33... two months would only cost you $41.... so you could still add the plan for the month that you need it and drop it and pay less than it would cost to have it for 6 months.
That said... once you have a problem, you might want to consider that the fix might not be a complete fix... it seems to me that it would be worth having the protection for 6 months in case you need someone to come back out and tweak something else within that period after the initial fix.