Some TV shows being added to my library waaay in the future

Let me explain.

I dropped my TV library as I wanted to totally start again using TVDB agent (was using something else). Anyway all was good, if a little slow, until I noticed that 4 or 5 old shows were showing in the recently added section before brand new episodes that had just aired. I investigated in the database and found that these 4 or 5 shows had been added with and updated_at or added_at date of 2038-01-01 for some odd reason.

So I ran some SQL to update the three affected tables

update media_items set updated_at = created_at where updated_at > date('2016-10-01');
update media_parts set updated_at = created_at where updated_at > date('2016-10-01');
update metadata_items set added_at = created_at where added_at > date('2016-10-01');

My actual questions though are

• Why would this happen in the first place

• Will my updates have affected anything else in the system adversely??

Thanks!

Mark