Handling DateTime and Node merges

So I have data coming in from two different timezones.
Both ISO 8601:

One looks like this: "2021-02-18T01:00:00+00:00"

The other like this: "2021-02-18T00:00:00+01:00"

They are essentially the same.

There is a Node N with a dateTime property called myTime in neo4j. How does Neo4j handle a merge over this property?

Merge (n:Node) where n.myTime = $newDateTime <set some other properties>

Do I have to make sure neo4j is using a dateTime?

Merge (n:Node) where dateTime(n.myTime ) = dateTime($newDateTime) <set some other properties>

What if I want the offset to be updated but no new node created?

Merge (n:Node) where dateTime(n.myTime ) = dateTime($newDateTime) set n.myTime = dateTime($newDateTime)

Will the property internally be handled as a dateTime now, or is it just a string?