I checked the labels table in the database, and the label creation date isn't there. The date the label was added to an issue might be accessible, as part of the change history, but you'd need to query the database to get that. I can't tell from your question if you're looking for a db query or JQL (JIRA Query Language), but I'll assume JQL for now.
Instead of label date, here's how you'd query for a label and for a value in a custom field called "Scheduled Release Date":
labels = maintenance and "Scheduled Release Date" >= "2017-01-01"
You can also do things like :
labels in (maintenance, upgrade) "Scheduled Release Date" >= startOfYear()