Problem with comparison of dates. S3 plugin

[ricardostocco]

When configuring the input s3 plugin I have a problem with comparing dates, since the last trace is re-processed, even though its update mark has not changed in the bucket.

I am NOT eliminating the files that are processed.

input {
s3 {
access_key_id => "xxxxx"
secret_access_key => "xxxx"
bucket => "xxxxx"
endpoint => "http://xxxxx.xxxxx.com"
region => "xxxxx"
proxy_uri => "http:/xxxx:xxxxx@xxxxxx:3128"
}
}

Logstash version: 7.0.1
SO: MS Windows 7
The bucket is not AWS S3, I'm using Open Cloud OBS (S3 compatible)

Example. In the file sincedb_xxx I have this date:
2019-05-20 23:45:10 +0000

and logstash reprocesses every 60 seconds a file that has an update date "2019-05-20 23:45:10 UTC"

It seems that the comparison "sincedb.newer? (Log.last_modified)" returns true when you compare those values ..

If I modify the comparison and compare integers, and it seems to work correctly ... (file s3.rb)

       def newer? (date)
         date.to_i> read.to_i
       end

Why is the comparison of dates wrong? Will the timezone be the problem? ("+0000" vs. "UTC")