How to handle Daylight Savings Time/Summer Time changes in Rivendell

Historical Narrative from 2018

Q: We are nearing the end of Daylight Savings Time. How do I add an extra hour so things work correctly in Rivendell?

A: RDLogEdit> select the log >Edit> Add your extra hour of audio carts

Comment: This is even more important in the fall, when 015959EDT is followed by 010000EST, and the entire hour is repeated.

A: This is handled by inserting a second 0100 hour, immediately after the first.

Comment: I can visualize -- though not at this moment describe -- some circumstances in which I could envision that breaking...

A: Here's one: hard start times in the "second" 0100 hour.

Q: I assume it doesn't actually cause too much trouble in practice?

A: Actually, it hasn't to date. We should find a less ad-hoc way to handle it though. We have eight months.

In the US the time change in the Autumn/Fall of the year is at 01:59:59 when the clock goes back to 01:00:00. I know some other parts of the world make the time change at other times of the night. In some areas the time change happens at 02:59:59 when the clock goes back to 02:00:00.

So to sum up, for the transition from Daylight savings time to Standard Time:

1) Add a second hour of programing to the log for the hour that will happen twice that night.

2) Do not use any hard start times in the second hour for the repeating hour in the log that would cause the log to jump from the first hour to the second hour in the log.

Precise Description for Fall Change to Standard Time from 2023

This description was posted to the Rivendell groups.io mailing list on 30 October, 2023 (edited for wiki formatting):

The fall time change is upon us once again. This Sunday, you will need to add an additional hour of programming between your normal 1am and 2am hours. There are several ways to handle inserting the additional programming. Regardless of which technique you use, it is important that you DO NOT:

A) Schedule a timed start event at exactly 2:00:00am.

B) Schedule two “1am” hours in the same log that both use timed starts within the body of the hour.

Remember, as the clock strikes 2am, the time is adjusted back to 1am, so the extra hour of programming needs to be inserted immediately after 1:59:59am. So, the inserted hour will occupy the second 1am hour of the day. We recommend not scheduling a timed event right at 2:00:00am as some systems may not process the time change quickly enough at the end of the first 1am hour to prevent a 2am timed event from firing an hour prematurely.

∗∗∗ Here are two suggested methods of handling the time change ∗∗∗

IF YOU NEED TO USE TIMED STARTS IN THE EXTRA HOUR OF PROGRAMMING

1. ) Generate the Sunday log as you do normally.
2. ) Open the Sunday log in RDLogEdit and use Save As to save a copy of the log using a different name. (We'll call this new log “Log B”).
3. ) In “Log B” delete all carts scheduled prior to 1am. (We will be chaining to this new log after the time change. The 1am hour in this log will be the second 1am hour played).
4. ) If the first cart in the new log has a timed start attribute set for 1:00:00am. Remove the timed start attribute. (We don't want the log to hang up if it doesn't get loaded in time to hit the timed start. The resulting log will have 23 hours of programming in it).
5. ) Save the changes made to “Log B”.
6. ) Open the original Sunday log in RDLogEdit.
7. ) Delete all carts scheduled after 1:59:59am. (This will leave you with a log with only 2 hours of programming in it).
8. ) Add a Log Chain marker at the end of the log that will chain to “Log B”. (This is done by selecting “Insert Meta” > “Log Chain”).

The result will be that the Saturday log will chain to the original Sunday log (that only contains 2 hours of programming). At 2am (now 1am) the original Sunday log will chain to the newly created “Log B”. Log B contains all of the programming from 1am to the end of the day where it will chain to the Monday log as usual.

IF YOU DO NOT NEED TO USE TIMED STARTS IN THE EXTRA HOUR OF PROGRAMMING

1. ) Generate the Sunday log as you do normally.
2. ) Use RDLogEdit to insert an extra hour of programming without any timed events in it.
3. ) Save the modified log.