What did timing belt job do to cause sputter?

I just had the timing belts, valve cover seals, and water pump replaced
on my 1990 Accord. Since picking it up on Wednesday, the car has had an
increasing sputter upon giving it gas, as if not all cylinders are
firing. Of course, it wouldn't do this on Thursday when I returned to
show them, but now it's clear most of the time and shouldn't be a
problem tomorrow. Not constant, and primarily evident when starting
from a stop (even stalled a couple of times while standing still). Any
ideas what I should expect them to fix, and if this is indeed something
traceable to the work they did?

 

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If it acts really gutless when COLD, but seems almost OK when it warms
up to temp, the timing belt is out one tooth. Very common error.
Sometimes fool mechanic adjusts the distributor timing to try to cover
up mistake, but it's not the same. Mileage will be terrible too.

Just for curiosity sake, ask them if they had to reset the ignition
timing after the belts were changed. If they say it was out several
degrees, they definitely got the TB out a tooth.

'Curly'

 

It was a bad valve seal other than the valve cover seal. The guy I
talked to, who was not the one who worked on it, claimed the guy who
did said it was "unrelated" but fixed it for free anyway. I didn't know
what to make of the "unrelated" comment, since it started right when I
got the car back. I asked why they didn't check those seals when they
were in there. He said I'd have to have specifically requested it.
Since I don't have a good pic of the engine with the valve cover off,
I'm not even sure where all of this is, so I don't know if this answer
was odd or not.