Date Mapping oddity

[Jeff_Bolle]

I have a date field in my data, but it is really only month and year (think credit card expiration dates). Here is the mapping in the index:
"date": {
"type": "date",
"ignore_malformed": true,
"format": "MM'/'yy||MM'/'yyyy||MMyy||MMyyyy"
}

When indexing a bunch of data, it comes close, but slightly misses on the dates:
String: 07/19
Date (when viewed in Kibana): June 30th 2019, 20:00:00.000
String: 10/17
Date (when viewed in Kibana): September 30th 2017, 20:00:00.000

"String" represents what is in the original string, "Date" represents what I see when looking in the data in Kibana. It almost feels like it is trying to do some sort of timezone adjustment or something.
Is there something I need to add to my format string? Any help or ideas would be appreciated. My other option is doing this in some additional back end code, but I'd really rather not, especially since ES is going to parse the date string anyway.

[warkolm (Mark Walkom)]

ES assumes UTC, KB changes to the TZ your browser is in.

So change your desktop TZ or change some of the advanced options in KB - https://www.elastic.co/guide/en/kibana/current/advanced-options.html

[Jeff_Bolle]

Thanks for the pointer there. I need the date timezone correction to work for other parts of Kibana, it is just this one place where it produces counter-intuitive results. As long as ES does queries based on the GMT time I think I will be fine.