Two things wrong with the answering machine. First, most of them play from the first message left and go to the newest one, not start at the newest one. Secondly, the message Strickland left was 1, but when Hank listens to the answering machine the one that is 1, is not from Strickland at all.
Tagline: "Look at me, I'm a kitty! Rawr" -Peggy
The calendar Strickland was looking in had all '97 dates. This episode takes place in '98 (or at least airs there). However it is quite possible that this was done because it was animated in '97 and they didn't think about it being aired in '98. Also he was looking at November and December, so it could be a calendar that is 16 months.
When Dale gives Peggy the can of water chestnuts her can of salt she had disappears.
When Dale approaches Peggy with a can of water chestnuts, we see her sprinkling ordinary table salt on the grass. In the winter, people sprinkle rock-salt, but on their sidewalks and driveways -not on grass! While this might be a joke about how little Texans know, Peggy is from Montana where it snows all the time. She should know a bit more about salting. If it was Hank then it might make more sense.
The bank clock says that it is 39 degrees outside, yet there is snow sticking to the ground.
When Hank notices Mr. Strickland is having a heart attack, he picks up the phone and dials 9-0-0, not 9-1-1.
(after Peggy has told him he won't be getting propane from Hank)
Dale: Fine. I'll just have to barter for it. (turns and yells across lawn) Bill! You like pumpkin-pie filling?
(Dale has just gifted Peggy some of his water chestnuts, and now wants a favor from her)
Dale: I only have a three-week supply of propane but you'll get Hank to hook me up. You owe me.
Peggy: Well, I'm sorry, Dale. Hank may be in charge now but you are not going to get any special treatment. Hank's priorities are propane first family second, friends third -- in that order.
Dale: (passing boxes to Joseph and Nancy in the basement/cellar) I bought enough canned food to last us through this storm and the civil unrest that will inevitably follow. (beat) Hope you like water chestnuts.
Bobby (as Buck commented that Bobby's on his way to being a propane man, and that he could one day fill his dad's shoes): But if I do that, where will my dad sit?
Buck: Well son, at the rate he's going, he'll be sitting in the boss' chair!
Hank: There's no need for that, sir. I'll just keep my own chair and wheel it up to your desk when the time comes.
Bobby: Look Ma, ash! There must be a volcano nearby!
Peggy: That's....snow! Everyone, stay calm. I've been through this before when I was in Montana. Nobody lick any flagpoles!
(Hank tries to remove Bobby from Buck's influential presence for a while)
Hank: Bobby, why don't you go outside and make snow angels.
Mr Strickland: Ooh hey, speakin' of angels, look at the wings on this angel! (Hank refrains from comment on the basis that the calendar girl is also Strickland Propane's cleaning lady!)
(After Hank gets a bit of a discount from Pa at the Ma & Pa store)
Ma: Now I know why they call you Pa; because you're pa-thetic
Pa: And I know why they call you Ma; 'cause you're always ridin' ma tail!
Dale: If you want, I can teach you how to make a bomb out of a roll of toilet paper and a stick of dynamite!
(Buck ogling the scenic Strickland Propane calendar..)
Bobby: Dad, how come I never got a Strickland calendar?
Hank: Uhh, that's not for you Bobby, you're not old enough.
Mr Strickland: Well, hello Miss November! You be careful, that's flammable, heh heh ha ha ha!
Peggy: (At the Strickland Propane cookout at the park) It's snowing! Alright, I have been through this before in Montana; now, nobody lick any flagpoles!
Hank: (At the company picnic in the park Snow!, Texans aren't prepared for this kind of nightmare sir; we gotta' work fast!
Hank: (realizing Buck uses an electric stove) Well, it had better be self-cleaning because I'm gonna vomit.
Although not mentioned at the time, it is later revealed that Strickland is married. It seems odd that the wife couldn't feed the dogs. Obviously, they hadn't decided on him being married when this episode was produced.
Strickland: That Vickers screwed up worse than Jack Kennedy at Piggy Bays.
Stickland is talking about President John F. Kennedy and the Bay of Pigs invasion which was an unsuccessful military invasion of Cuba on April 17th 1961.