Standards
Time zone vs UTC offset: what is the difference?
A UTC offset is today’s number. A time zone is the named rule set that can calculate the right local time for a particular place and date.
An offset answers one narrow question
A UTC offset tells you the difference between UTC and a local clock at a particular instant. It is excellent for displaying a finished conversion, but it carries no information about where the rule came from or when it may change.
An IANA identifier carries rules
An IANA identifier such as Europe/Paris or America/New_York identifies a representative location and its known civil-time transitions. It lets a program calculate the correct offset for a past or future date, including daylight saving time.
Store the place with the event
For a future meeting, record the local wall time, date and time-zone identifier. Do not store only the current offset. If the jurisdiction changes its clocks before the meeting, updated time-zone data can apply the revised rule.