The teleport spell says:

This spell instantly transports you and up to eight willing creatures
of your choice that you can see within range, or a single object that
you can see within range, to a destination you select. If you target
an object, it must be able to fit entirely inside a 10-foot cube, and
it can't be held or carried by an unwilling creature.

My reading of it has been that you can teleport

(a) you and up to eight willing creatures
or

(b) a single object

But is this correct? It could also be parsed as

(a) You
and

(b) up to eight willing creatures or a single object

Can a caster teleport himself and that 8 foot tall gold statue of Elvis? Or does this require two castings?

Later wording in the spell seems to reinforce the first interpretation:

You and your group (or the target object) appear where you want to.

but I'd like to know if this has been addressed in designer tweets, errata, or elsewhere within the RAW.

You can target a yourself and a group of creatures, or target just an object

While this hasn't been clarified anywhere, the grammar and structure of the spell description itself is enough to come to a conclusion.

This spell instantly transports you and up to eight willing creatures
of your choice that you can see within range, or a single object that
you can see within range, to a destination you select.

Not a couple things about this. First it is presented as two complete conditions:

This spell instantly transports:

1. you and up to eight willing creatures of your choice that you can see within range

or

2. a single object that you can see within range

Note the ever important comma after the first condition showing that what follows is separate from it. If it had been intended to be read the other way it would have been written like this:

This spell instantly transports you and up to eight willing creatures, or you and a single object of your choice, that you can see within range to a destination you select.

This is then (as you pointed out) supported by a later passage:

You and your group (or the target object) appear where you want to.

Taken together it is clear: you can teleport you and a group of creatures or you can teleport an object. You cannot teleport yourself and an object with the same casting.