When you use TSM, you're kind of committing to respond to the craving when it shows up by using the One Hour Rule. White knuckling is generally counter-productive in this context. Don't be thrown off by your numbers climbing back up again, that happens most of the time. Perhaps focus on some way of controlling the latter part of your drinking session, like taking a sip and then getting the glass out of your sight and getting up to a little 10 or 15 minute task. Then ask yourself if you really want another sip, notice how your're feeling and be aware of the what's going on inside you that drives you to retrieve the glass. Break things up and make it harder for the automatic part of your habit to take complete control, listen for the point of "meh", watch for the indifference. This is something that will take practice, but you'll have a smoother journey for it.

Note also that when you have a big decrease in your drinking, it may well be followed by an increase, which may be followed by a further notch down.

I'm having the same problem FWIW--three weeks in my weekly count was down, and then last week a disaster---several nights I lost count so I just guessed when I filled in my totals for the week.