Re: Subject + verb ("intended") + infinitive phrase. Could the phrase function as an adverb (vs. direct object)?

First, to save time and effort, I do understand simple explanations such as this (owl.purdue.edu):

We intended to leave early.

The infinitive phrase functions as the direct object of the verb
intended.

to leave (infinitive)

early (adverb)

But I can’t imagine how an infinitive phrase following the verb intended could function as anything other than a direct object.

I don’t see the difference between that example and this one (grammar.yourdictionary.com):

Joshua intended to write a novel during his sabbatical. (modifying
the verb “intended”)

This example is listed under Used as Adverbs. There is a discussion at the bottom of the page:

Q: Joshua intended: Doesn’t the infinitive answer what?

A: It answers when–read the rest of the phrase!

I realize that no one should rely on any online discussion (or dictionary) for grammar tips, but I think I’m missing something in this case (perhaps the big picture).

As I mentioned, I don’t see the difference, so I would break it down like this:

Joshua intended to write a novel during his sabbatical.

The infinitive phrase functions as the direct object of the verb intended.

to write (infinitive)

a novel (direct object, infinitive’s own)

during his sabbatical (adverbial PP; when to write)

Questions

Is that breakdown accurate (at least traditionally), and if not, would you point out my errors (or major issues), please?

Also, from the title, could the verb intended (or any transitive verb, if you wish to elaborate) be followed by an adverbial infinitive phrase (or clause) versus one that functions as a direct object?

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Thank you.

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