I think he was correcting the part of post #2 that says
"No one at AT&T (or any other carrier) will tell you ahead of time what these will be".
[doublepost=1516213086][/doublepost]
Your phone bill would go up $5/month (if you setup AutoPay to a debit card or with a check, which gives you a $10 discount on the new plan). So you're talking $145/month (new plan) vs $140/month (old plan).
The new plan would lower your DTV bill by $15/month, and the free HBO should be worth at least $10/month.
So your phone bill goes up $5/month but you get $25/month in TV discounts...
That sounds like a $20 net savings for you. Plus you get tethering and the other features
@boltjames mentioned above.