This is a sentence from Manhattan SC After many years of

This is a sentence from Manhattan SC

After many years of difficult negotiations, a deal has been reached that will lower tariffs and end
many subsidies, potentially changing the lives of millions of people in both the developed and the
developing world.

main clause is - a deal has been reached

this main clause is modified by the essential modifier (releative clause) - "that will lower tariffs and end many subsidies"

this is followed a ",verbing" modifier - , potentially changing the lives of millions of people in both the developed and the
developing world.

i have read the discussion on verbing modifiers.

the question i have is : in a construction identical to the one above, will the verbing modify the releative clase which immediately precedes it?

or will it modify the main clause of the sentance?

i went through the explanation given under "verbing modifiers part 2"

In the past several years, astronomers have detected more than 80 massive planets, most of them at least as large as Jupiter, circling other stars.

(leaving the idiom issues aside)

it says circling is verbing modifier without the COMMA (since the comma belongs to the non essential phrase , most of them at least as large as Jupiter,)

so circling is a present participle which modifies plants

I am ok with this explanation.

My question is that

After many years of difficult negotiations, a deal has been reached that will lower tariffs and end
many subsidies, potentially changing the lives of millions of people in both the developed and the
developing world.

in the above sentance, clearly ",potentially changing" is an adverbial modifier (not a noun modifier like in the previous example)

so will changing modify the clause

1. that will lower tariffs and end many subsidies

or

2. a deal has been reached

Any help is greatly appreciated.