Extra station codes on SLE tickets

I took Shore Line East recently, and I bought the ticket on-board for the first time. On the passenger receipt, it has a listing of station codes that are punched through as you would expect... but there's 4 station codes between the codes for Old Saybrook and Westbrook that just do not exist on Shore Line East at all. They are ESX, CHT, MDT, and HFD, which I intuitively guess are Essex, Chester, Middletown, and Hartford on the Valley Line. Anyone know why they bothered to put these on the tickets/receipts?

I'm pretty sure those were codes for DATTCO bus stops. I have a timetable somewhere from 15 years ago showing select Old Saybrook-New London trains paired with select DATTCO busses to/from Hartford. I suppose the intention was to try to boost ridership on New London trains by having commuters get onboard @ NLC, take the train to OSB, and then switch to the bus towards Hartford in the morning and the other way around in the evening.

Why they're still on the ticket receipts is anyone's guess, but I guess CDOT decided it wasn't necessary to have new ticket receipts reworked and printed with those stops removed. If you look closely you'll see "REV. 4-99" printed in small type just above the "CT Commuter Rail" logo. So they've been using the same receipts for over 16 years!

I rode SLE last Friday and my receipt says "FORM No. NRCP 52 REV. 04-15". If they were revised April 2015, still makes me wonder why Essex, Chester, Middletown, and Hartford are shown.

There used to be a sign in the parking lot in front of the Amtrak station building that said "EXPRESS COMMUTER BUS TO HARTFORD BOARDS HERE" (or something to that effect). It hasn't been shown in the timetable in years, though, and most likely was eliminated when New London service was reduced several years ago. Later, it was increased to what we have today.

9 Town Transit, which operates Middletown-OSB limited stop buses as well as local buses from OSB to Madison, NLC, and Chester accepts SLE tickets for a free transfer.